Keywords: Selfish genetic elements

The ultra-selfish gene

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Mathias Kirk Bonde,  Works in Progress,  2024.
Almost every cell in our bodies contains 23 pairs of chromosomes, which are packages of the DNA and genes that provide the code for producing living things. Sperm and egg cells, however, each contain only one set of chromosomes. This set of chromosomes has been recombined from ...

Autosomal suppression of sex-ratio meiotic drive influences the dynamics of X and Y chromosome coevolution

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Anjali Gupta, Robert L Unckless,  Journal of Heredity,  2024.
Sex-ratio meiotic drivers are selfish genes or gene complexes that bias the transmission of sex chromosomes resulting in skewed sex ratios. Existing theoretical models have suggested the maintenance of a four-chromosome equilibrium (with driving and standard X and suppressing and ...

Functional and evolutionary constraints of wtf killer meiotic drivers

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Ananya Nidamangala Srinivasa, Samuel Campbell, Shriram Venkatesan, Nicole L Nuckolls, Jeffrey J Lange, Randal Halfmann, Sarah E Zanders,  bioRxiv,  2024.
Killer meiotic drivers are selfish DNA loci that sabotage the gametes that do not inherit them from a driver+/driver- heterozygote. These drivers often employ toxic proteins that target essential cellular functions to cause the destruction of driver- gametes. Identifying the ...

An egg-sabotaging mechanism drives non-Mendelian transmission in mice

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Frances E. Clark, Naomi L. Greenberg, Duilio M.Z.A. Silva, et al,  Current Biology,  2024.
Selfish genetic elements drive in meiosis to distort their transmission ratio and increase their representation in gametes, violating Mendel’s law of segregation. The two established paradigms for meiotic drive, gamete killing and biased segregation, are fundamentally ...

Male-killing virus leads to more female moths

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Anonymous,  Nature,  2023.
Keisuke Nagamine at Minami Kyushu University in Miyazaki, Japan, and his colleagues have identified another virus that kills male embryos of the tobacco caterpillar, Spodoptera litura. Female moths infected with the virus produced an equal number of male and female embryos, but ...

Male-killing virus in a noctuid moth Spodoptera litura

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K. Nagamine, Y. Kanno, K. Sahara, T. Fujimoto, A. Yoshido, Y. Ishikawa, M. Terao, D. Kageyama and Y. Shintani,  Proceedings of the National Academy of Sciences,  120:e2312124120. 2023.
A female-biased sex ratio is considered advantageous for the cytoplasmic elements that inhabit sexually reproducing organisms. There are numerous examples of bacterial symbionts in the arthropod cytoplasm that bias the host sex ratio toward females through various means, ...

Gene drive in plants emerges from infancy

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M. J. A. Awan, R. Z. Naqvi, I. Amin and S. Mansoor,  Trends in Plant Science,  2023.
Selfish genetic elements (SGEs) display biased transmission to offspring. However, their breeding potential has remained obscure. Wang et al. recently reported a natural gene-drive system that can be harnessed to prevent hybrid incompatibility and to develop a synthetic ...

New perspectives on the causes and consequences of male meiotic drive

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Courret, Cécile Wei, Xiaolu Larracuente, Amanda M.,  Current Opinion in Genetics & Development,  2023.
Gametogenesis is vulnerable to selfish genetic elements that bias their transmission to the next generation by cheating meiosis. These so-called meiotic drivers are widespread in plants, animals, and fungi and can impact genome evolution. Here, we summarize recent progress on the ...

The role of conflict in shaping plant biodiversity

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J. M. Coughlan,  New Phytologist,  2023.
Although intrinsic postzygotic reproductive barriers can play a fundamental role in speciation, their underlying evolutionary causes are widely debated. One hypothesis is that incompatibilities result from genomic conflicts. Here, I synthesize the evidence that conflict generates ...

Proliferation and dissemination of killer meiotic drive loci

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E. C. Lai and A. A. Vogan,  Current Opinion in Genetics and Development,  82:102100. 2023.
Killer meiotic drive elements are selfish genetic entities that manipulate the sexual cycle to promote their own inheritance via destructive means. Two broad classes are sperm killers, typical of animals and plants, and spore killers, which are present in ascomycete fungi. Killer ...

Ability of a selfish B chromosome to evade genome elimination in the jewel wasp, Nasonia vitripennis

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H. Lee, P. Seo, S. Teklay, E. Yuguchi, E. D. Benetta, J. H. Werren and P. M. Ferree,  Heredity,  2023.
B chromosomes are non-essential, extra chromosomes that can exhibit transmission-enhancing behaviors, including meiotic drive, mitotic drive, and induction of genome elimination, in plants and animals. A fundamental but poorly understood question is what characteristics allow B ...

X chromosome drive is constrained by sexual selection and influences ornament evolution

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K. A. Paczolt, G. T. Welsh and G. S. Wilkinson,  Proceedings of the Royal Society B: Biological Sciences,  290:20230929. 2023.
Experimental evolution provides an integrative method for revealing complex interactions among evolutionary processes. One such interaction involves sex-linked selfish genetic elements and sexual selection. X-linked segregation distorters, a type of selfish genetic element, ...

Impacts of sex ratio meiotic drive on genome structure and function in a stalk-eyed fly

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J. A. Reinhardt, R. H. Baker, A. V. Zimin, C. Ladias, K. A. Paczolt, J. H. Werren, C. Y. Hayashi and G. S. Wilkinson,  Genome Biology Evolution,  2023.
Stalk-eyed flies in the genus Teleopsis carry selfish genetic elements that induce sex ratio meiotic drive (SR) and impact the fitness of male and female carriers. Here, we assemble and describe a chromosome-level genome assembly of the stalk-eyed fly, Teleopsis dalmanni, to ...

Cell biology: Selfish B chromosomes unleashed by a dysfunctional chromosome segregation system

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P. Ferree,  Current Biology,  33:R431-R434. 2023.
A study in the fruit fly Drosophila melanogaster shows that a defective chromosome segregation system allows non-essential B chromosomes to transmit at higher-than-Mendelian frequencies.

Cell biology: Selfish B chromosomes unleashed by a dysfunctional chromosome segregation system

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P. Ferree,  Current Biology,  33:R431-R434. 2023.
A study in the fruit fly Drosophila melanogaster shows that a defective chromosome segregation system allows non-essential B chromosomes to transmit at higher-than-Mendelian frequencies. Higher eukaryotes harbor a range of different selfish genetic elements (SGEs). One type of ...

Adaptation in the face of internal conflict: the paradox of the organism revisited

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M. M. Patten, M. A. Schenkel and J. A. Ågren,  Biological Reviews,  2023.
The paradox of the organism refers to the observation that organisms appear to function as coherent purposeful entities, despite the potential for within-organismal components like selfish genetic elements and cancer cells to erode them from within. While it is commonly accepted ...

A gene drive is a gene drive: the debate over lumping or splitting definitions

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S. L. James, D. A. O'Brochta, F. Randazzo and O. Akbari,  Nature Communications,  2023.
Gene drive technologies are being considered as a new approach to address a variety of currently intractable global problems, including to prevent disease transmission, reduce crop loss, and preserve biodiversity1. There are some outside the genetics research community who argue ...

Gene Drives Are Coming

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D. Lowe,  Science,  2023.
Consider the “gene drive” idea - there are a lot of variations, but the general idea is that you introduce a genetic sequence into an organism that can bias (drive) its own inheritance into the next generation. This is a thumb-on-the-scale unnatural selection if ever there ...

Effects of Wolbachia on Transposable Element Expression Vary Between Drosophila melanogaster Host Genotypes

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A. T. Eugénio, M. S. P. Marialva and P. Beldade,  Genome Biology Evolution,  15. 2023.
Transposable elements (TEs) are repetitive DNA sequences capable of changing position in host genomes, thereby causing mutations. TE insertions typically have deleterious effects but they can also be beneficial. Increasing evidence of the contribution of TEs to adaptive evolution ...

Expansion and loss of sperm nuclear basic protein genes in Drosophila correspond with genetic conflicts between sex chromosomes

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C.-H. Chang, I. Mejia Natividad and H. S. Malik,  eLife,  12:e85249. 2023.
Many animal species employ sperm nuclear basic proteins (SNBPs) or protamines to package sperm genomes tightly. SNBPs vary across animal lineages and evolve rapidly in mammals. We used a phylogenomic approach to investigate SNBP diversification in Drosophila species. We found ...

A selfish genetic element and its suppressor causes gross damage to testes in a fly

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S. Lyth, A. Manser, G. Hurst, T. Price and R. Verspoor,  bioRxiv,  2023.02.06.527273. 2023.
Selfish genetic elements (SGEs), specifically X-chromosome meiotic drive (XCMD), create huge conflicts within a hosts genome and can have profound effects on fertility. Suppressors are a common evolutionary response to XCMD to negate its costs. However, whether suppressors ...

Complicated expansion trajectories of insertion sequences and potential association with horizontal transfer of Wolbachia DNA

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Y. H. Miao, D. W. Huang and J. H. Xiao,  Zoological Research,  44:273-275. 2023.
Insertion sequences (ISs) are the simplest structural transposable elements (TEs) in prokaryotes, consisting only of a transposase coding sequence and its bilateral short terminal inverted repeats. Due to their gradually streamlined genomic construction, TEs rarely exist in the ...

P-element invasions in Drosophila erecta; shed light on the establishment of host control over a transposable element

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D. Selvaraju, F. Wierzbicki and R. Kofler,  bioRxiv,  2022.12.22.521571. 2022.
To prevent the spread of transposable elements (TEs) hosts have developed sophisticated defence mechanisms. In mammals and invertebrates this defence mechanism operates through piRNAs. It is unclear how piRNA-based defences are established against invading TEs. According to the ...

How Selfish Genes Succeed: Critical Insights Uncovered About Dangerous DNA

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STOWERS INSTITUTE FOR MEDICAL RESEARCH,  SciTechDaily,  2022.
New findings from the Stowers Institute for Medical Research uncover critical insights about how a dangerous selfish gene—considered to be a parasitic portion of DNA—functions and survives. Understanding this dynamic is a valuable resource for the broader community studying ...

How selfish genes succeed

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Stowers Institute for Medical Research,  ScienceDaily,  2022.
A new study reveals how a selfish gene in yeast uses a poison-antidote strategy that enables its function and likely has facilitated its long-term evolutionary success. This strategy is an important addition for scientists studying similar systems including teams that are ...

Meiotic transmission patterns of additional genomic elements in Brachionus asplanchnoidis, a rotifer with intraspecific genome size variation

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J. Blommaert and C.-P. Stelzer,  Scientific Reports,  12:20900. 2022.
Intraspecific genome size (GS) variation in Eukaryotes is often mediated by additional, nonessential genomic elements. Physically, such additional elements may be represented by supernumerary (B-)chromosomes or by large heterozygous insertions into the regular chromosome set. ...

Discovery of 119-Million-Year-Old “Selfish” Genes Casts Doubt on Established Evolution Beliefs

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Stowers Institute for Medical Research,  SciTechDaily,  2022.
Meiotic drivers, a kind of selfish gene, are indeed selfish. They are found in virtually all species’ genomes, including humans, and unjustly transfer their genetic material to more than half of their offspring, resulting in infertility and impaired organism health. Their ...

Discovery of 119-Million year old Selfish Genes Casts Doubt on Established Evolution Beliefs

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Stowers Institute for Medical Research,  Stowers Institute for Medical Research,  2022.

119-Million-Year-Old “Selfish” Genes Uncovered in Yeast

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Stowers Institute for Medical Research,  Technology Networks,  2022.
Meiotic drivers, a type of selfish gene, are indeed selfish. Present in the genomes of nearly all species, including humans, they unfairly transfer their genetic material to more than half of their offspring, sometimes leading to infertility, and decreased organism health. ...

The wtf meiotic driver gene family has unexpectedly persisted for over 100 million years

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M. De Carvalho, G. S. Jia, A. Nidamangala Srinivasa, R. B. Billmyre, Y. H. Xu, J. J. Lange, I. M. Sabbarini, L. L. Du and S. E. Zanders,  eLife,  11. 2022.
Meiotic drivers are selfish elements that bias their own transmission into more than half of the viable progeny produced by a driver+/driver- heterozygote. Meiotic drivers are thought to exist for relatively short evolutionary timespans because a driver gene or gene family is ...

Selfish evolution of placental hormones

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G. Keegan and M. M. Patten,  Evolution, Medicine, and Public Health,  10:391-397. 2022.
We hypothesize that some placental hormones—specifically those that arise by tandem duplication of genes for maternal hormones—may behave as gestational drivers, selfish genetic elements that encourage the spontaneous abortion of offspring that fail to inherit them. Such ...

On the Mechanistic Basis of Killer Meiotic Drive in Fungi

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S. J. Saupe and H. Johannesson,  Annual Review of Microbiology,  76:305-323. 2022.
Spore killers are specific genetic elements in fungi that kill sexual spores that do not contain them. A range of studies in the last few years have provided the long-awaited first insights into the molecular mechanistic aspects of spore killing in different fungal models, ...

B Chromosomes in Psalidodon scabripinnis (Characiformes, Characidae) Species Complex

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D. Silva, J. P. Castro, C. A. G. Goes, R. Utsunomia, M. R. Vidal, C. N. Nascimento, L. F. Lasmar, F. G. Paim, L. B. Soares, C. Oliveira, F. Porto-Foresti, R. F. Artoni and F. Foresti,  Animals (Basel),  12. 2022.
B chromosomes are extra-genomic components of cells found in individuals and in populations of some eukaryotic organisms. They have been described since the first observations of chromosomes, but several aspects of their biology remain enigmatic. Despite being present in hundreds ...

Reflection on the Challenges, Accomplishments, and New Frontiers of Gene Drives

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M. Melesse Vergara, J. Labbé and J. Tannous,  BioDesign Research,  2022:9853416. 2022.
Ongoing pest and disease outbreaks pose a serious threat to human, crop, and animal lives, emphasizing the need for constantgenetic discoveries that could serve as mitigation strategies. Gene drives are genetic engineering approaches discovered decadesago that may allow quick, ...

Non-Mendelian transmission of accessory chromosomes in fungi

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J. Komluski, E. H. Stukenbrock and M. Habig,  Chromosome Research,  2022.
Non-Mendelian transmission has been reported for various genetic elements, ranging from small transposons to entire chromosomes. One prime example of such a transmission pattern are B chromosomes in plants and animals. Accessory chromosomes in fungi are similar to B chromosomes ...

“Selfish Genetic Elements” – Supergene Wreaks Havoc in a Genome

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University of Rochester,  SciTechDaily,  2022.
“Selfish genetic elements” litter the human genome. They do not seem to benefit their hosts but instead seek only to propagate themselves. These selfish genetic elements can wreak havoc. For example, they can distort sex ratios, impair fertility, cause harmful mutations, and ...

What can we learn from selfish loci that break Mendel’s law?

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S. E. Zanders,  PLOS Biology,  20:e3001700. 2022.
Mendel’s law of segregation provides a critical foundation for genetic inquiry It is not, however, without exceptions Historically, 2 such exceptions (sex chromosome linkage and chromosome missegregation in meiosis) were used by Drosophila geneticists to help demonstrate ...

Isolation of rfk-2 (UV) , a mutation that blocks spore killing by Neurospora Spore killer-3

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A. Velazquez, E. Webber, D. O'Neil, T. Hammond and N. Rhoades,  MicroPublication Biology,  2022.
Neurospora Spore killer-3 ( Sk-3 ) is a selfish genetic element that kills spores to achieve gene drive.  Here, to help identify Sk-3’s killer, we performed a genetic screen for required for killing (rfk) mutations (see methods). The genetic screen uses Sk‑3 rskΔ × SkS ...

A Toxin-Antidote Selfish Element Increases Fitness of its Host

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L. Long, W. Xu, A. B. Paaby and P. T. McGrath,  bioRxiv,  2022.07.15.500229. 2022.
Selfish genetic elements can promote their transmission at the expense of individual survival, creating conflict between the element and the rest of the genome. Recently, a large number of toxin-antidote (TA) post-segregation distorters have been identified in non-obligate ...

Iterative evolution of supergene-based social polymorphism in ants

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T. Kay, Q. Helleu and L. Keller,  Philos Trans R Soc Lond B Biol Sci,  377:20210196. 2022.
Species commonly exhibit alternative morphs, with individual fate being determined during development by either genetic factors, environmental cues or a combination thereof. Ants offer an interesting case study because many species are polymorphic in their social structure. Some ...

Unbalanced selection: the challenge of maintaining a social polymorphism when a supergene is selfish

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A. G. Tafreshi, S. P. Otto and M. Chapuisat,  Philos Trans R Soc Lond B Biol Sci,  377:20210197. 2022.
Supergenes often have multiple phenotypic effects, including unexpected detrimental ones, because recombination suppression maintains associations among co-adapted alleles but also allows the accumulation of recessive deleterious mutations and selfish genetic elements. Yet, ...

Supergene potential of a selfish centromere

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F. Finseth, K. Brown, A. Demaree and L. Fishman,  Philos Trans R Soc Lond B Biol Sci,  377:20210208. 2022.
Selfishly evolving centromeres bias their transmission by exploiting the asymmetry of female meiosis and preferentially segregating to the egg. Such female meiotic drive systems have the potential to be supergenes, with multiple linked loci contributing to drive costs or ...

Active genetics comes alive

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V. M. Gantz and E. Bier,  BioEssays,  2022.
Abstract Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based ?active genetic? elements developed in 2015 bypassed the fundamental rules of traditional genetics. Inherited in a super-Mendelian fashion, such selfish genetic entities offered a variety of ...

Non-Mendelian segregation and transmission drive of B chromosomes

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J. P. M. Camacho,  Chromosome Research,  2022.
Selfish genetic elements (SGE) get a transmission advantage (drive) thanks to their non-Mendelian inheritance. Here I identify eight steps during the reproductive cycle that can be subverted by SGEs to thrive in natural populations. Even though only three steps occur during ...

Mendelian nightmares: the germline-restricted chromosome of songbirds

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P. Borodin, A. Chen, W. Forstmeier, S. Fouché, L. Malinovskaya, Y. Pei, R. Reifová, F. J. Ruiz-Ruano, S. A. Schlebusch, M. Sotelo-Muñoz, A. Torgasheva, N. Vontzou and A. Suh,  Chromosome Res,  2022.
Germline-restricted chromosomes (GRCs) are accessory chromosomes that occur only in germ cells. They are eliminated from somatic cells through programmed DNA elimination during embryo development. GRCs have been observed in several unrelated animal taxa and show peculiar modes of ...

The non-Mendelian behavior of plant B chromosomes

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J. Chen, J. A. Birchler and A. Houben,  Chromosome Res,  2022.
B chromosomes, also known as supernumerary chromosomes, are dispensable elements in the genome of many plants, animals, and fungi. Many B chromosomes have evolved one or more drive mechanisms to transmit themselves at a higher frequency than predicted by Mendelian genetics, and ...

B-A Chromosome Translocations Possessing an A Centromere Partly Overcome the Root-Restricted Process of Chromosome Elimination in Aegilops speltoides

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D. Li, A. Ruban, J. Fuchs, H. Kang and A. Houben,  Frontiers in Cell and Developmental Biology,  10. 2022.
Some eukaryotes exhibit dramatic genome size differences between cells of different organs, resulting from the programmed elimination of chromosomes. Aegilops speltoides is an annual diploid species from the Poaceae family, with a maximum number of eight B chromosomes (Bs) in ...

Evolution of eukaryotic centromeres by drive and suppression of selfish genetic elements

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T. Kumon and M. A. Lampson,  Seminars in Cell and Developmental Biology,  2022.
Despite the universal requirement for faithful chromosome segregation, eukaryotic centromeres are rapidly evolving. It is hypothesized that rapid centromere evolution represents an evolutionary arms race between selfish genetic elements that drive, or propagate at the expense of ...

Genetic Drive Systems in Nature

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David O'Brochta and Hector Quemada,  GeneConvene Global Collaborative,  2022.
Intra genomic genetic conflicts are ubiquitous in nature and have shaped and continue to shape the evolution of plants, animals, and microbes. These conflicts can result in preferential transmission - drive - of genes, various genetic elements, and even whole chromosomes. ...

Endosymbionts moderate constrained sex allocation in a haplodiploid thrips species in a temperature-sensitive way

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A. Katlav, D. T. Nguyen, J. L. Morrow, R. N. Spooner-Hart and M. Riegler,  Heredity,  9. 2022.
Maternally inherited bacterial endosymbionts that affect host fitness are common in nature. Some endosymbionts colonise host populations by reproductive manipulations (such as cytoplasmic incompatibility; CI) that increase the reproductive fitness of infected over uninfected ...

Gene drive that results in addiction to a temperature-sensitive version of an essential gene triggers population collapse in Drosophila

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G. Oberhofer, T. Ivy and B. A. Hay,  Proceedings of the National Academy of Sciences,  118:e2107413118. 2021.
One strategy for population suppression seeks to use gene drive to spread genes that confer conditional lethality or sterility, providing a way of combining population modification with suppression. Stimuli of potential interest could be introduced by humans, such as an otherwise ...

Molecular Mechanisms and Evolutionary Consequences of Spore Killers in Ascomycetes

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S. Zanders and H. Johannesson,  Microbiology and Molecular Biology Reviews,  2021.
In this review, we examine the fungal spore killers. These are meiotic drive elements that cheat during sexual reproduction to increase their transmission into the next generation. Spore killing has been detected in a number of ascomycete genera, including Podospora, Neurospora, ...

A Maternal-Effect Toxin Affects Epithelial Differentiation and Tissue Mechanics in Caenorhabditis elegans

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C. Lehmann and C. Pohl,  Frontiers in Cell and Developmental Biology,  9. 2021.
Selfish genetic elements that act as post-segregation distorters cause lethality in non-carrier individuals after fertilization. Two post-segregation distorters have been previously identified in Caenorhabditis elegans, the peel-1/zeel-1 and the sup-35/pha-1 elements. These ...

Meiotic self-pairing of the Psalidodon (Characiformes, Characidae) iso-B chromosome: A successful perpetuation mechanism

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D. Silva, C. Araya-Jaime, M. Yamashita, M. R. Vidal, C. Oliveira, F. Porto-Foresti, R. F. Artoni and F. Foresti,  Genetics and Molecular Biology,  44:e20210084. 2021.
B chromosomes are non-essential additional genomic elements present in several animal and plant species. In fishes, species of the genus Psalidodon (Characiformes, Characidae) harbor great karyotype diversity, and multiple populations carry different types of non-essential B ...

Evolutionary robustness of killer meiotic drives

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P. G. Madgwick and J. B. Wolf,  Evolution Letters,  2021.
A meiotic driver is a selfish genetic element that interferes with the process of meiosis to promote its own transmission. The most common mechanism of interference is gamete killing, where the meiotic driver kills gametes that do not contain it. A killer meiotic driver is ...

Unravelling the mystery of female meiotic drive: where we are

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F. E. Clark and T. Akera,  Open Biol,  11:210074. 2021.
Female meiotic drive is the phenomenon where a selfish genetic element alters chromosome segregation during female meiosis to segregate to the egg and transmit to the next generation more frequently than Mendelian expectation. While several examples of female meiotic drive have ...

Parallel pathways for recruiting effector proteins determine centromere drive and suppression

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T. Kumon, J. Ma, R. B. Akins, D. Stefanik, C. E. Nordgren, J. Kim, M. T. Levine and M. A. Lampson,  Cell,  2021.
Selfish centromere DNA sequences bias their transmission to the egg in female meiosis. Evolutionary theory suggests that centromere proteins evolve to suppress costs of this "centromere drive." In hybrid mouse models with genetically different maternal and paternal centromeres, ...

Haldane’s duel: intragenomic conflict, selfish Y chromosomes and speciation

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S. W. Roy,  Trends in Genetics,  2021.
Haldane?s rule, which states that the heterogametic sex (XY or ZW females) fares more poorly in interspecific hybrids, is generally attributed to absence of one of the two species' X/Z chromosomes. However, Haldane?s rule is also observed in mouse placentas despite paternal X ...

Researchers report reference genome for maize B chromosome

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Chinese Academy of Sciences,  Phys Org,  2021.
Three groups recently reported a reference sequence for the supernumerary B chromosome in maize in a study published online in PNAS. Dr. James Birchler's group from University of Missouri, Dr. Jan Barto's group from Institute of Experimental Botany of the Czech Academy of ...

Selfish gene leaves bacteria behind

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A. York,  Nature Reviews Microbiology,  2021.
Mitochondrial genome evolution is characterized by functional streamlining and gene loss, and gain-of-function gene transfers into the mitochondrial genome are considered rare events. Milner, et al. identified a functional restriction modification (R-M) system in the ...

Mechanistically comparing reproductive manipulations caused by selfish chromosomes and bacterial symbionts

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E. Dalla Benetta, O. S. Akbari and P. M. Ferree,  Heredity,  126:707-716. 2021.
Insects naturally harbor a broad range of selfish agents that can manipulate their reproduction and development, often leading to host sex ratio distortion. Such effects directly benefit the spread of the selfish agents. These agents include two broad groups: bacterial symbionts ...

A functional bacteria-derived restriction modification system in the mitochondrion of a heterotrophic protist

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D. A.-O. Milner, J. A.-O. Wideman, C. A.-O. Stairs, C. D. Dunn and T. A.-O. Richards,  PLoS Biology,  2021.
The overarching trend in mitochondrial genome evolution is functional streamlining coupled with gene loss. Therefore, gene acquisition by mitochondria is considered to be exceedingly rare. Selfish elements in the form of self-splicing introns occur in many organellar genomes, but ...

Invasion and maintenance of meiotic drivers in populations of ascomycete fungi

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I. Martinossi-Allibert, C. Veller, S. L. Ament-Velasquez, A. A. Vogan, C. Rueffler and H. Johannesson,  Evolution,  20. 2021.
Meiotic drivers (MDs) are selfish genetic elements that are able to become overrepresented among the products of meiosis. This transmission advantage makes it possible for them to spread in a population even when they impose fitness costs on their host organisms. Whether an MD ...

Regulating the expression of gene drives is key to increasing their invasive potential and the mitigation of resistance

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A. Hammond, X. Karlsson, I. Morianou, K. Kyrou, A. Beaghton, M. Gribble, N. Kranjc, R. Galizi, A. Burt, A. Crisanti and T. Nolan,  PLOS Genetics,  17:e1009321. 2021.
Here we show that restricting the cutting activity of the gene drive to the germline tissue is crucial to maintaining its potency and we illustrate how failure to restrict this activity can lead to the generation of mutations that can make mosquitoes resistant to the gene drive.

Widespread haploid-biased gene expression enables sperm-level natural selection

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K. Bhutani, K. Stansifer, S. Ticau, L. Bojic, A.-C. Villani, J. Slisz, C. M. Cremers, C. Roy, J. Donovan, B. Fiske and R. C. Friedman,  Science,  eabb1723. 2021.
Here, we show that a large class of mammalian genes are not completely shared across these bridges. We term these genes “genoinformative markers” (GIMs) and show that a subset can act as selfish genetic elements that spread alleles unevenly through murine, bovine, and human ...

Self-Deleting Genes Project To Tackle Mosquito-Borne Diseases

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D. Ozdemir,  INTERESTING ENGINEERING,  2021.
Did you know that mosquitoes kill at least 725,000 persons every year? They truly are one of the world's deadliest animals which is the reason why scientists from all around are trying to find new ways of dealing with them. Controlling mosquito populations and preventing them ...

Edit, undo: Temporary gene editing could help solve the mosquito problem

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L. Dormehl,  digitaltrends,  2020.
But if SyFy original movies have taught us anything, it’s that genetically tweaking organisms and then releasing them can… well, not go quite according to plan.With that in mind, a new Texas A&M AgriLife Research project seeks to test out genetic modifications of mosquitos ...

Self-deleting genes promise risk-free genetic engineering of mosquitoes

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D. Quick,  New Atlas,  2020.
A new project by Texas A&M AgriLife Research is looking to enable "test runs" of genetic changes to mosquitoes that are automatically deleted. Various angles of attack using genetic engineering to combat mosquitoes have been pursued in recent years, including modifying them so ...

Self-deleting genes to be tested as part of mosquito population control concept

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B. Hays,  UPI,  2020.
Scientists at Texas A&M have developed a new technique for altering the genes of mosquitoes -- the new technology will cause genetic changes to self-delete from the mosquitoes' genome. Thanks to the breakthrough, described Monday in the Philosophical Transactions of the Royal ...

$3.9M project on self-deleting genes takes aim at mosquito-borne diseases

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O. Kuchment,  AGRILIFE Today,  2020.
To control mosquito populations and prevent them from transmitting diseases such as malaria, many researchers are pursuing strategies in mosquito genetic engineering. A new Texas A&M AgriLife Research project aims to enable temporary “test runs” of proposed genetic changes in ...

Self-deleting genes tested as part of the concept of mosquito population control

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charlottelarson,  NEWYORK NEWS TIMES,  2020.
Most genetic engineering strategies designed to control mosquito populations, and their ability to spread diseases such as malaria, require gene editing to be combined with gene drives. Gene drives allow altered DNA to spread rapidly throughout the population.

Making gene drive biodegradable

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J. Zapletal, N. Najmitabrizi, M. Erraguntla, M. A. Lawley, K. M. Myles and Z. N. Adelman,  Philosophical Transactions of the Royal Society B: Biological Sciences,  376:20190804. 2020.
Here, we consider the inclusion of self-elimination mechanisms into the design of homing-based gene drive transgenes. This approach not only caused the excision of the gene drive transgene, but also generates a transgene-free allele resistant to further action by the gene drive. ...

X-linked meiotic drive can boost population size and persistence

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C. Mackintosh, A. Pomiankowski and M. F. Scott,  Genetics,  217:11. 2020.
Here, we find general conditions for the spread and fixation of X-linked alleles. Our conditions show that the spread of X-linked alleles depends on sex-specific selection and transmission rather than the time spent in each sex. Applying this logic to meiotic drive, we show that ...

Mosquito genomes are frequently invaded by transposable elements through horizontal transfer

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E. S. de Melo and G. L. Wallau,  PLOS Genetics,  16:e1008946. 2020.
We characterized the whole TE content of 24 mosquito genomes and investigated the TE inheritance mode uncovering hundreds of horizontal transfer events among these species and distantly related ones. We also identify a mosquito parasitic filarial worm, th

Sequence analysis in Bos taurus reveals pervasiveness of X–Y arms races in mammalian lineages

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J. F. Hughes, H. Skaletsky, T. Pyntikova, N. Koutseva, T. Raudsepp, L. G. Brown, D. W. Bellott, T.-J. Cho, S. Dugan-Rocha, Z. Khan, C. Kremitzki, C. Fronick, T. A. Graves-Lindsay, L. Fulton, W. C. Warren, R. K. Wilson, E. Owens, J. E. Womack, W. J. Murphy,  Genome Research,  2020.
Here, we provide evidence that suppression of X–Y crossing-over unleashed a second dynamic: selfish X–Y arms races that reshaped the sex chromosomes in mammals as different as cattle, mice, and men. Using super-resolution sequencing, we explore the Y Chromosome of Bos taurus ...

The bull Y chromosome has evolved to bully its way into gametes

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Whitehead Institute for Biomedical Research,  Phys Org,  2020.
In a new study, published Nov. 18 in the journal Genome Research, scientists in the lab of Whitehead Institute Member David Page present the first ever full, high-resolution sequence of the Y chromosome of a Hereford bull. The research, more than a decade in the making, suggests ...

Resistance to natural and synthetic gene drive systems

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T. A. R. Price, N. Windbichler, R. L. Unckless, A. Sutter, J.-N. Runge, P. A. Ross, A. Pomiankowski, N. L. Nuckolls, C. Montchamp-Moreau, N. Mideo, O. Y. Martin, A. Manser, M. Legros, A. M. Larracuente, L. Holman, J. Godwin, N. Gemmell, C. Courret, A. Buc,  Journal of Evolutionary Biology,  2020.
This review summarizes our current knowledge of drive resistance in both natural and synthetic gene drives. We explore how insights from naturally occurring and synthetic drive systems can be integrated to improve the design of gene drives, better predict the outcome of releases ...

Invasion and maintenance of spore killers in populations of ascomycete fungi

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I. Martinossi-Allibert, C. Veller, S. L. Ament-Velásquez, A. A. Vogan, C. Rueffler and H. Johannesson,  bioRxiv,  2020.04.06.026989. 2020.
We show how ploidy level, rate of selfing, and efficiency of spore killing affect the invasion probability of a driving allele and the conditions for its stable coexistence with the non-driving allele. Our model can be adapted to different fungal life-cycles, and is applied here ...

The Enterprise: A massive transposon carrying Spokt meiotic drive genes

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A. A. Vogan, S. L. Ament-Velásquez, E. Bastiaans, O. Wallerman, S. J. Saupe, A. Suh and H. Johannesson,  bioRxiv,  2020.03.25.007153. 2020.
Previously, we described a large genomic feature called the Spok block which is notable due to the presence of meiotic drive genes of the Spok gene family. The Spok block ranges from 110 kb to 247 kb and can be present in at least four different genomic locations within P. ...

Selfish genes and sexual selection: the impact of genomic parasites on host reproduction

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N. Wedell,  Journal of Zoology,  311:1-12. 2020.
Selfish genetic elements (SGEs) such as replicating mobile elements, segregation distorters and maternally inherited endosymbionts, bias their transmission success relative to the rest of the genome to increase in representation in subsequent generations. As such, they generate ...

Gene drive and resilience through renewal with next generation Cleave and Rescue selfish genetic elements

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G. Oberhofer, T. Ivy and B. A. Hay,  Proceedings of the National Academy of Sciences,  117:9013-9021. 2020.
Gene drive can spread beneficial traits through populations, but will never be a one-shot project in which one genetic element provides all desired modifications, for an indefinitely long time. Here, we show that gene drive-mediated population modification in Drosophila can be ...

Autosomal suppression and fitness costs of an old driving X chromosome in Drosophila testacea

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G. Keais, S. Lu and S. Perlman,  Journal of Evolutionary Biology,  2020.
Driving X chromosomes (XDs) are meiotic drivers that bias their own transmission through males by killing Y-bearing gametes. These chromosomes can in theory spread rapidly in populations and cause extinction, but many are found as balanced polymorphisms or as ?cryptic? XDs shut ...

An X-linked meiotic drive allele has strong, recessive fitness costs in female Drosophila pseudoobscura

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W. Larner, T. Price, L. Holman and N. Wedell,  Proceedings of the Royal Society B-Biological Sciences,  286:9. 2019.
Selfish 'meiotic drive' alleles are transmitted to more than 50% of offspring, allowing them to rapidly invade populations even if they reduce the fitness of individuals carrying them. Theory predicts that drivers should either fix or go extinct, yet some drivers defy these ...

The impact of local population genetic background on the spread of the selfish element Medea-1 in red flour beetles

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S. A. Cash, M. A. Robert, M. D. Lorenzen and F. Gould,  Ecology and Evolution,  12:1-12. 2019.
Selfish genetic elements have been found in the genomes of many species, yet our understanding of their evolutionary dynamics is only partially understood. A number of distinct selfish Medea elements are naturally present in many populations of the red flour beetle (Tribolium ...

The distribution and spread of naturally occurring Medea selfish genetic elements in the United States

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S. A. Cash, M. D. Lorenzen and F. Gould,  Ecology and Evolution,  9:14407–14416.. 2019.
Selfish genetic elements (SGEs) are DNA sequences that are transmitted to viable offspring in greater than Mendelian frequencies. Medea SGEs occur naturally in some populations of red flour beetle (Tribolium castaneum) and are expected to increase in frequency within populations ...

Fitness consequences of the selfish supergene Segregation Distorter

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H. W. S. Wong and L. Holman,  Journal of Evolutionary Biology,  33:89-100. 2019.
Segregation distorters are selfish genetic elements that subvert Mendelian inheritance, often by destroying gametes that do not carry the distorter. Simple theoretical models predict that distorter alleles will either spread to fixation or stabilize at some high intermediate ...

Evolutionary simulations of Z-linked suppression gene drives

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L. Holman,  Proceedings of the Royal Society B-Biological Sciences,  286:1-9. 2019.
Synthetic gene drives may soon be used to suppress or eliminate populations of disease vectors, pathogens, invasive species, and agricultural pests. Recent proposals have focused on using Z-linked gene drives to control species with ZW sex determination, which include ...

Standard deviations: The biological bases of transmission ratio distortion

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L. Fishman and M. McIntosh,  Annual Review of Genetics,  53:347-372. 2019.
The rule of Mendelian inheritance is remarkably robust, but deviations from the equal transmission of alternative alleles at a locus [a.k.a. transmission ratio distortion (TRD)] are also commonly observed in genetic mapping populations. Such TRD reveals locus-specific selection ...

Combinations of Spok genes create multiple meiotic drivers in Podospora

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A. A. Vogan, S. L. Ament-Velásquez, A. Granger-Farbos, J. Svedberg, E. Bastiaans, A. J. M. Debets, V. Coustou, H. Yvanne, C. Clavé, S. J. Saupe and H. Johannesson,  eLife,  8:e46454. 2019.
Meiotic drive is the preferential transmission of a particular allele during sexual reproduction. The phenomenon is observed as spore killing in multiple fungi. In natural populations of Podospora anserina, seven spore killer types (Psks) have been identified through classical ...

A family of killers

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M. De Carvalho and S. E. Zanders,  eLife,  8:e49211. 2019.
Spok genes are meiotic drivers that increase their own chances of transmission by killing gametes that do not inherit them.

B chromosome first—mechanisms behind the drive of B chromosomes uncovered

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Leibniz Institute of Plant Genetics and Crop Plant Research,  Phy Org,  2019.
The specific number of chromosomes is one of the defining characteristics of a species. Whilst the common fruit fly carries 8 chromosomes, the genome of bread wheat counts 42 chromosomes. In comparison, the human genome is made out of a total of 46 chromosomes. However, about 15% ...

Identification of fk-1;, a Meiotic Driver Undergoing RNA Editing in Neurospora

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N. A. Rhoades, A. M. Harvey, D. A. Samarajeewa, J. Svedberg, A. Yusifov, A. Abusharekh, P. Manitchotpisit, D. W. Brown, K. J. Sharp, D. G. Rehard, J. Peters, X. Ostolaza-Maldonado, J. Stephenson, P. K. T. Shiu, H. Johannesson and T. M. Hammond,  Genetics,  212:93. 2019.
These findings indicate that unedited and edited rfk-1 transcripts exist and that these transcripts could have different roles with respect to the mechanism of meiotic drive by spore killing. Regardless of RNA editing, spore killing only succeeds if rfk-1 transcripts avoid ...

Spatial structure undermines parasite suppression by gene drive cargo

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Bull, JJR, Christopher H.; Gomulkiewicz, Richard; Krone, Stephen M.,  PeerJ,  7:e7921. 2019.
Gene drives may be used in two ways to curtail vectored diseases. Both involve engineering the drive to spread in the vector population. One approach uses the drive to directly depress vector numbers, possibly to extinction. The other approach leaves intact the vector population ...

The toxin–antidote model of cytoplasmic incompatibility: Genetics and evolutionary implications

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Beckmann, JFB, Manon; Chen, Hongli; Hochstrasser, Mark; Poinsot, Denis; Merçot, Hervé; Weill, Mylène; Sicard, Mathieu; Charlat, Sylvain,  Trends in Genetics,  35:175-185. 2019.
Wolbachia bacteria inhabit the cells of about half of all arthropod species, an unparalleled success stemming in large part from selfish invasive strategies. Cytoplasmic incompatibility (CI), whereby the symbiont makes itself essential to embryo viability, is the most common of ...

Engineered Reciprocal Chromosome Translocations Drive High Threshold, Reversible Population Replacement in Drosophila

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Buchman, ABI, Tobin; Marshall, John M.; Akbari, Omar S.; Hay, Bruce A.,  ACS Synthetic Biology,  7:1359-1370. 2018.
Replacement of wild insect populations with transgene-bearing individuals unable to transmit disease or survive under specific environmental conditions using gene drive provides a self-perpetuating method of disease prevention. Mechanisms that require the gene drive element and ...

Genetic villains: Killer meiotic drivers

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Bravo Núñez, MAN, Nicole L.; Zanders, Sarah E.,  Trends in Genetics,  34:424-433. 2018.
Unbiased allele transmission into progeny is a fundamental genetic concept canonized as Mendel’s Law of Segregation. Not all alleles, however, abide by the law. Killer meiotic drivers are ultra-selfish DNA sequences that are transmitted into more than half (sometimes all) of ...

Rapid comeback of males: evolution of male-killer suppression in a green lacewing population

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Hayashi, MN, M.; Kageyama, D.,  Proceedings of the Royal Society B-Biological Sciences,  285:6. 2018.
Evolutionary theory predicts that the spread of cytoplasmic sex ratio distorters leads to the evolution of host nuclear suppressors, although there are extremely few empirical observations of this phenomenon. Here, we demonstrate that a nuclear suppressor of a cytoplasmic male ...

Selfish genetic elements

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Agren, JAC, A. G.,  PLOS Genetics,  14:20. 2018.
Selfish genetic elements (historically also referred to as selfish genes, ultra-selfish genes, selfish DNA, parasitic DNA, genomic outlaws) are genetic segments that can enhance their own transmission at the expense of other genes in the genome, even if this has no or a negative ...

Strong hybrid male incompatibilities impede the spread of a selfish chromosome between populations of a fly

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Verspoor Rudi, LSJ, M. L.; Mannion Natasha, L. M.; Hurst Gregory, D. D.; Price Tom, A. R.,  Evolution Letters,  2:169-179. 2018.
Meiotically driving sex chromosomes manipulate gametogenesis to increase their transmission at a cost to the rest of the genome. The intragenomic conflicts they produce have major impacts on the ecology and evolution of their host species. However, their ecological dynamics ...

How selfish DNA hijacks its way into egg cells

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Science Magazine,  Science,  2017.

Spindle asymmetry drives non-Mendelian chromosome segregation

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T. Akera, L. Chmátal, E. Trimm, K. Yang, C. Aonbangkhen, D. M. Chenoweth, C. Janke, R. M. Schultz and M. A. Lampson,  Science,  358:668. 2017.
Genetic elements compete for transmission through meiosis, when haploid gametes are created from a diploid parent. Selfish elements can enhance their transmission through a process known as meiotic drive. In female meiosis, selfish elements drive by preferentially attaching to ...

A maternal-effect selfish genetic element in Caenorhabditis elegans

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E. Ben-David, A. Burga and L. Kruglyak,  Science,  356:1051. 2017.
We discovered a selfish element causing embryonic lethality in crosses between wild strains of the nematode Caenorhabditis elegans.

Poisons, antidotes, and selfish genes

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N. Phadnis,  Science,  356:1013. 2017.
On page1051 of this issue, BenDavid et al . (3) chase down a serendipitous observation of an anomaly in genetic crosses to unmask a toxin-antidote type of selfish system in worms.

Meiotic drive changes sperm precedence patterns in house mice: potential for male alternative mating tactics?

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Sutter, AL, A. K.,  BMC Evolutionary Biology,  16:15. 2016.
Background: With female multiple mating (polyandry), male-male competition extends to after copulation (sperm competition). Males respond to this selective pressure through physiological, morphological and behavioural adaptations. Sperm competitiveness is commonly decreased in ...

The Impact of Dissociation on Transposon-Mediated Disease Control Strategies

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J. M. Marshall,  Genetics,  178:1673-1682. 2008.
Vector-borne diseases such as malaria and dengue fever continue to be a major health concern through much of the world. The emergence of chloroquine-resistant strains of malaria and insecticide-resistant mosquitoes emphasize the need for novel methods of disease control. ...

Population dynamics of transposable elements: Copy number regulation and species invasion requirements

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Struchiner, CJK, M. G.; Ribeiro, J. M. C.,  Journal of Biological Systems,  13:455-475. 2005.
A deterministic population dynamics model of the spread of transposable elements (TE) in sexually reproducing populations is presented. The population is modeled by a three-parameter equation describing host reproductive capacity, population size and the strength of the density ...

B chromosomes and genome size in flowering plants

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Trivers, RB, A.; Palestis, B. G.,  Genome,  47:1-8. 2004.
B chromosomes are extra chromosomes found in some, but not all, individuals within a species, often maintained by giving themselves an advantage in transmission, i.e. they drive. Here we show that the presence of B chromosomes correlates to and varies strongly and positively with ...

Mariner transposition and transformation of the yellow fever mosquito, Aedes aegypti

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C. J. Coates, N. Jasinskiene, L. Miyashiro and A. A. James,  Proceedings of the National Academy of Sciences of the United States of America,  95:3748-3751. 1998.
The mariner transposable element is capable of interplasmid transposition in the embryonic soma of the yellow fever mosquito, Aedes aegypti. To determine if this demonstrated mobility could be utilized to genetically transform the mosquito, a modified mariner element marked with ...

Stable transformation of the yellow fever mosquito, Aedes aegypti, with the Hermes element from the housefly

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N. Jasinskiene, C. J. Coates, M. Q. Benedict, A. J. Cornel, C. S. Rafferty, A. A. James and F. H. Collins,  Proceedings of the National Academy of Sciences of the United States of America,  95:3743-3747. 1998.
The mosquito Aedes aegypti is the world's most important vector of yellow fever and dengue viruses, Work is currently in progress to control the transmission of these viruses by genetically altering the capacity of wild Ae, aegypti populations to support virus replication. The ...

Selfish DNA and breeding system in flowering plants

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Burt, AT, R.,  Proceedings of the Royal Society B-Biological Sciences,  265:141-146. 1998.
In many species, some individuals carry one or more B chromosomes: extra, or supernumerary chromosomes not part of the normal complement. In most well-studied cases, B's lower the fitness of their carrier and persist in populations only because of accumulation mechanisms ...

Gene transfer into the Medfly, Ceratitis capitata, using a Drosophila hydei transposable element.

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T. G. Loukeris, I. Livadaras, B. Arca, S. Zabalou and C. Savakis,  Science,  270:2002-2005. 1995.
Exogenous functional DNA was introduced into the germline chromosomes of the Mediterranean fruit fly (medfly) Ceratitis capitata with a germline transformation system based on the transposable element Minos from Drosophila hydei. Transformants were identified as phenotypic ...

Rapid spread of transposable P elements in experimental populations of Drosophila melanogaster.

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A. G. Good, G. A. Meister, H. W. Brock, T. A. Grigliatti and D. A. Hickey,  Genetics,  1223:387-396. 1989.
The invasion of P elements in natural populations of Drosophila melanogaster was modeled by establishing laboratory populations with 1 %, 5% and 10% P genomes and monitoring the populations for 20 generations. In one experiment, the ability of flies to either induce or suppress ...

Genetic-transformation of Drosophila with transposable element vectors

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G. M. Rubin and A. C. Spradling,  Science,  218:348-353. 1982.
Exogenous DNA sequences were introduced into the Drosophila germ line. A rosy transposon (ry1), constructed by inserting a chromosomal DNA fragment containing the wild-type rosy gene into a P transposable element, transformed germ line cells in 20 to 50 percent of the injected ...

Mutable loci in maize.

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B. McClintock,  Carnegie Inst. Washington Year Book,  47:155-169. 1948.
Previous reports have state that the number of unstable loci have recently arisen in maize culture. In a particular cell of a plant, a normal "wild-type" locus becomes altered; the normal, dominant expression of this locus changes and gives rise to a recessive expression (or, in ...