Keywords: b chromosomes

Sequence of the supernumerary B chromosome of maize provides insight into its drive mechanism and evolution

N. Blavet, H. Yang, H. Su, P. Solanský, R. N. Douglas, M. Karafiátová, L. Šimková, J. Zhang, Y. Liu, J. Hou, X. Shi, C. Chen, M. El-Walid, M. E. McCaw, P. S. Albert, Z. Gao, C. Zhao, G. Ben-Zvi, L. Glick, G. Kol, J. Shi, J. Vrána, H. Šimková, J. C. Lamb,,  Proceedings of the National Academy of Sciences,  118:e2104254118. 2021.
B chromosomes are nonvital chromosomes found in thousands of plants and animals that persist through various drive mechanisms. The drive mechanism of the maize B chromosome consists of mitotic nondisjunction at the second pollen division to produce two unequal sperm and then the ...
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Nondisjunction and unequal spindle organization accompany the drive of Aegilops speltoides B chromosomes

D. Wu, A. Ruban, J. Fuchs, J. Macas, P. Novák, M. Vaio, Y. Zhou and A. Houben,  New Phytologist,  223:1340-1352. 2021.
B chromosomes (Bs) are supernumerary chromosomes, which are often preferentially inherited. When transmission rates of chromosomes are higher than 0.5, not obeying the Mendelian law of equal segregation, the resulting transmission advantage is collectively referred to as ...
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Researchers report reference genome for maize B chromosome

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 ...
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Mechanistically comparing reproductive manipulations caused by selfish chromosomes and bacterial symbionts

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 ...
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Interpopulation spread of a parasitic B chromosome is unlikely through males in the grasshopper Eyprepocnemis plorans

M. I. Manrique-Poyato, J. Cabrero, M. D. López-León, F. Perfectti, R. Gómez and J. P. M. Camacho,  Heredity,  124:197-206. 2019.
The near-neutral model of B chromosome evolution predicts that population invasion is quite fast. To test this prediction, in 1994, we introduced males of the grasshopper Eyprepocnemis plorans from a B-carrying population into a B-lacking population and monitored the evolution of ...
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B chromosome first—mechanisms behind the drive of B chromosomes uncovered

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% ...
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Origin, composition, and structure of the supernumerary B chromosome of Drosophila melanogaster

Hanlon, SLM, Danny E.; Eche, Salam; Hawley, R. Scott,  Genetics,  210:1197. 2018.
The number of chromosomes carried by an individual species is one of its defining characteristics. Some species, however, can also carry supernumerary chromosomes referred to as B chromosomes. B chromosomes were recently identified in a laboratory stock of Drosophila ...
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Satellite DNAs unveil clues about the ancestry and composition of B chromosomes in three grasshopper species

Milani, DB, Vanessa; Ferretti, Ana; Palacios-Gimenez, Octavio; Melo, Adriana; Moura, Rita; Loreto, Vilma; Song, Hojun; Cabral-de-Mello, Diogo,  Genes,  9:e523. 2018.
Supernumerary (B) chromosomes are dispensable genomic elements occurring frequently among grasshoppers. Most B chromosomes are enriched with repetitive DNAs, including satellite DNAs (satDNAs) that could be implicated in their evolution. Although studied in some species, the ...
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B Chromosomes in populations of mammals revisited

Vujoševi?, MR, Marija; Blagojevi?, Jelena,  Genes,  9:487. 2018.
The study of B chromosomes (Bs) started more than a century ago, while their presence in mammals dates since 1965. As the past two decades have seen huge progress in application of molecular techniques, we decided to throw a glance on new data on Bs in mammals and to review them. ...
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Gene drive: Evolved and synthetic

Burt, AC, Andrea,  ACS Chemical Biology,  13:343-346. 2018.
Drive is a process of accelerated inheritance from one generation to the next that allows some genes to spread rapidly through populations even if they do not contribute to—or indeed even if they detract from—organismal survival and reproduction. Genetic elements that can ...
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Transmission and drive involving parasitic B chromosomes

Jones, RN,  Genes,  9:e388. 2018.
B chromosomes (Bs) are enigmatic additional elements in the genomes of thousands of species of plants, animals, and fungi. How do these non-essential, harmful, and parasitic chromosomes maintain their presence in their hosts, making demands on all the essential functions of their ...
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B chromosome in Plantago lagopus Linnaeus, 1753 shows preferential transmission and accumulation through unusual processes

Dhar, MKK, G.; Kaul, S.,  Comparative Cytogenetics,  11:375-391. 2017.
Plantago lagopus is a diploid (2n = 2x = 12) weed belonging to family Plantaginaceae. We reported a novel B chromosome in this species composed of 5S and 45S ribosomal DNA and other repetitive elements. In the present work, presence of B chromosome(s) was confirmed through FISH ...
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Preferential accumulation of sex and Bs chromosomes in biarmed karyotypes by meiotic drive and rates of chromosomal changes in fishes

Molina, WFM, P. A.; Bertollo, L. A. C.; Bidau, C. J.,  Anais Da Academia Brasileira De Ciencias,  86:1801-1812. 2014.
Mechanisms of accumulation based on typical centromeric drive or of chromosomes carrying pericentric inversions are adjusted to the general karyotype differentiation in the principal Actinopterygii orders. Here, we show that meiotic drive in fish is also supported by preferential ...
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Transmission rate variation among three B chromosome variants in the fish Prochilodus lineatus (Characiformes, Prochilodontidae)

Penitente, MV, T. A.; Senhorini, J. A.; Bortolozzi, J.; Foresti, F.; Porto-Foresti, F.,  Anais Da Academia Brasileira De Ciencias,  85:1371-1377. 2013.
Cytogenetic studies were developed in Prochilodus lineatus (Valenciennes 1836), describing an interesting system of small supernumerary chromosomes. The purpose of this work is to study the frequency and morphology of B chromosomes in individuals from the parental line and the ...
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Spread of a new parasitic B chromosome variant is facilitated by high gene flow

Manrique-Poyato, MIL-L, M. D.; Cabrero, J.; Perfectti, F.; Camacho, J. P. M.,  PLOS One,  8:e83712. 2013.
The B-24 chromosome variant emerged several decades ago in a Spanish population of the grasshopper Eyprepocnemis plorans and is currently reaching adjacent populations. Here we report, for the first time, how a parasitic B chromosome (a strictly vertically transmitted parasite) ...
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B chromosomes in plants

Jones, N,  Plant Biosystems,  146:727-737. 2012.
B chromosomes (Bs) can be described as "selfish chromosomes", a term that has been used for the repetitive DNA which comprises the bulk of the genome in large genome species, except that Bs have a life of their own as independent chromosomes. They can accumulate in number by ...
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Nondisjunction in favor of a Chromosome: The mechanism of rye B chromosome drive during pollen mitosis

Banaei-Moghaddam, AMS, V.; Kumke, K.; Weiss, O.; Klemme, S.; Nagaki, K.; Macas, J.; Gonzalez-Sanchez, M.; Heredia, V.; Gomez-Revilla, D.; Gonzalez-Garcia, M.; Vega, J. M.; Puertas, M. J.; Houben, A.,  Plant Cell,  24:4124-4134. 2012.
B chromosomes (Bs) are supernumerary components of the genome and do not confer any advantages on the organisms that harbor them. The maintenance of Bs in natural populations is possible by their transmission at higher than Mendelian frequencies. Although drive is the key for ...
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B Chromosomes and Sex in Animals

Camacho, JPMS, M.; Cabrero, J.,  Sexual Development,  5:155-166. 2011.
Supernumerary (B) chromosomes are dispensable elements found in many eukaryote genomes in addition to standard (A) chromosomes. In many respects, B chromosomes resemble sex chromosomes, so that a common ancestry for them has frequently been suggested. For instance, B chromosomes ...
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B chromosomes and genome size in flowering plants

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 ...
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Rapid suppression of drive for a parasitic B chromosome

Perfectti, FC, J. M.; Mesa, J. A.; Cabrero, J.; Bakkali, M.; Lopez-Leon, M. D.; Camacho, J. P. M.,  Cytogenetic and Genome Research,  106:338-343. 2004.
The persistence of parasitic B chromosomes in natural populations depends on both B ability to drive and host response to counteracting it. In the grasshopper Eyprepocnemis plorans, the B-24 chromosome is the most widespread B chromosome variant in the Torrox area ( Malaga, ...
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The distribution of B chromosomes across species

Palestis, BGT, R.; Burt, A.; Jones, R. N.,  Cytogenetic and Genome Research,  106:151-158. 2004.
In this review we look at the broad picture of how B chromosomes are distributed across a wide range of species. We review recent studies of the factors associated with the presence of Bs across species, and provide new analyses with updated data and additional variables. The ...
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B chromosomes are more frequent in mammals with acrocentric karyotypes: support for the theory of centromeric drive

Palestis, BGB, A.; Jones, R. N.; Trivers, R.,  Proceedings of the Royal Society B-Biological Sciences,  271:S22-S24. 2004.
The chromosomes of mammals tend to be either mostly acrocentric (having one long arm) or mostly bi-armed, with few species having intermediate karyotypes. The theory of centromeric drive suggests that this observation reflects a bias during female meiosis, favouring either more ...
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Mapping of paternal-sex-ratio deletion chromosomes localizes multiple regions involved in expression and transmission

McAllister, BFB, L. W.; Werren, J. H.,  Heredity,  92:5-13. 2004.
The paternal-sex-ratio (PSR) chromosome in the parasitic wasp Nasonia vitripennis is a submetacentric supernumerary (B chromosome). Males transmit PSR, but after fertilization it causes the loss of the paternal autosomes. Paternal genome loss caused by PSR results in the ...
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B chromosomes in Sternorrhyncha (Hemiptera, Insecta)

Maryanska-Nadachowska, A,  Cytogenetic and Genome Research,  106:210-214. 2004.
In the hemipteroid insects of the suborder Sternorrhyncha, B chromosomes are relatively common in comparison with other suborders of Hemiptera. However, the occurrence of supernumerary chromosomes is restricted, in most cases, to several genera or closely related species. At ...
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The B chromosome polymorphism of the grasshopper Eyprepocnemis plorans in North Africa. IV. Transmission of rare B chromosome variants

Bakkali, MC, J. P. M.,  Cytogenetic and Genome Research,  106:332-337. 2004.
In addition to the principal B chromosome (B-1) in Moroccan populations of the grasshopper Eyprepocnemis plorans, nine B chromosome variants appeared at low frequency. The transmission of five of these rare B chromosome variants through females was analysed in three natural ...
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B chromosomes in plants: escapees from the A chromosome genome?

Jones, NH, A.,  Trends in Plant Science,  8:417-423. 2003.
B chromosomes are dispensable elements that do not recombine with the A chromosomes of the regular complement and that follow their own evolutionary track. In some cases, they are known to be nuclear parasites with autonomous modes of inheritance, exploiting 'drive' to ensure ...
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Localization of the genes controlling B chromosome transmission rate in maize (Zea mays ssp. mays, Poaceae)

Chiavarino, AMR, M.; Rosi, P.; Poggio, L.; Naranjo, C. A.,  American Journal of Botany,  85:1581-1585. 1998.
In previous papers we found that the frequency of B chromosomes in native races of maize varies considerably in different populations. Moreover, we found genotypes that control high and low transmission rates (TR) of B chromosomes in the Pisingallo race. In the present work ...
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Selfish DNA and breeding system in flowering plants

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 ...
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Genetic control of B chromosome transmission rate in Zea mays ssp mays (Poaceae)

Rosato, MC, A. M.; Naranjo, C. A.; Puertas, M. J.; Poggio, L.,  American Journal of Botany,  83:1107-1112. 1996.
We selected genotypes of high and low B chromosome transmission rate (TR) in a native race of maize (Pisingallo) from northwest Argentina. We made 20 female 0B x male 1B and 20 f.1B x m.0B crosses. The former (G0m) showed a large variation of B TR, with a mean of TR +/- SE = 0.52 ...
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The effect of B chromosomes on mating success of the grasshopper Eyprepocnemis plorans

Martin, SA, P.; HenriquesGil, N.,  Genetica,  97:197-203. 1996.
The mating ability of E. plorans was tested in laboratory conditions in six experimental units composed of ten males and fifteen females during 31 days. When significant differences were found (three from the six cages, and in totals) they involved a decrease of matings involving ...
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Evidence for B chromosome drive suppression in the grasshopper Eyprepocnemis plorans

Herrera, JAL, M. D.; Cabrero, J.; Shaw, M. W.; Camacho, J. P. M.,  Heredity,  76:633-639. 1996.
The grasshopper Eyprepocnemis plorans is polymorphic for both a B chromosome and a heterochromatic segment of chromatin on the smallest autosome. Females transmit these to their offspring more frequently after copulating with a male from a population without Bs than after ...
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The inheritance of B chromosomes in Allium schoenoprasum L

Bougourd, SMP, A. B.,  Chromosome Research,  4:151-158. 1996.
The inheritance of B chromosomes has been investigated in Allium schoenoprasum from the River Wye, Powys; controlled crosses between plants of known B chromosome constitution were carried out, and the numbers of Bs present in the progenies scored. There was considerable ...
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Bewildering Bs – An impression of the 1st B-chromosome conference

Beukeboom, LW,  Heredity,  73:328-336. 1994.
Ever since their first discovery B chromosomes have attracted attention. Why are they so appealing? The standard chromosomes of an organism are A chromosomes; B chromosomes are extra to this normal complement. In the B chromosome 'bible' (Jones & Rees, 1982) Bs are defined as ...
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Deletion analysis of the selfish B-chromosome, Paternal Sex-Ratio (PSR), in the parasitic wasp Nasonia vitripennis

Beukeboom, LWW, J. H.,  Genetics,  133:637-648. 1993.
Paternal Sex Ratio (PSR) is a ''selfish'' B chromosome in the parasitoid wasp Nasonia vitripennis. It is transmitted via sperm, but causes supercondensation and destruction of the paternal chromosomes in early fertilized eggs. Because this wasp has haplodiploid sex determination, ...
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Transmission and expression of the parasitic Paternal Sex-Ratio (PSR) chromosome

Beukeboom, LWW, J. H.,  Heredity,  70:437-443. 1993.
B-chromosomes are often considered genomic parasites. They are extra to the normal chromosomal complement, are unnecessary for survival of an individual, and are often inherited at higher than Mendelian rates. Paternal Sex Ratio (PSR) is an extreme example of a parasitic ...
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Meiotic behavior of B- chromosomes in the grasshopper Omocestus burri: A case of drive in females

Santos, JLD, A. L.; Fernandez, A.; Diez, M.,  Hereditas,  118:139-143. 1993.
The meiotic behaviour of an iso-B chromosome of the grasshopper Omocestus burri has been studied in a natural population located at Villar del Cobo (Teruel, Spain) by means of cytological observations of male and female meiosis. Whereas B chromosomes do not accumulate in the male ...
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Male and female segregation distortion for heterochromatic supernumerary segments on the s(8) chromosome of the grasshopper Chorthippus jacobsi

Lopezleon, MDC, J.; Camacho, J. P. M.,  Chromosoma,  101:511-516. 1992.
The mode of inheritance of supernumerary segments located on three different chromosome pairs was investigated in controlled crosses with specimens of the grasshopper Chorthippus jacobsi. While extra segments located on chromosomes M5 and M6 showed Mendelian inheritance, that on ...
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Population genetics of a parasitic chromosome – Experimental analysis of PSR in subdivided populaltions

Beukeboom, LWW, J. H.,  Evolution,  46:1257-1268. 1992.
Nasonia vitripennis is a parasitoid wasp that harbors several non-Mendelian sex-ratio distorters. These include MSR (Maternal Sex Ratio), a cytoplasmic element that causes nearly all-female families, and PSR (Paternal Sex Ratio), a supernumerary chromosome that causes all-male ...
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Effects of deletions on mitotic stability of the Paternal Sex-Ratio (PSR) chromosome from Nasonia

Beukeboom, LWR, K. M.; Werren, J. H.,  Chromosoma,  102:20-26. 1992.
Paternal-Sex-Ratio (PSR) is a B chromosome that causes all-male offspring in the parasitoid wasp Nasonia vitripennis. It is only transmitted via sperm of carrier males and destroys the other paternal chromosomes during the first mitotic division of the fertilized egg. Because of ...
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The paternal-sex-ratio chromosome of Nasonia

Werren, JH,  American Naturalist,  137:392-402. 1991.
Paternal sex ratio (PSR) is a supernumerary chromosome that is transmitted through sperm to fertilized eggs and then gains a transmission advantage by causing supercondensation of the paternal chromosomes (except itself). Because of haplodiploidy, this converts diploid females ...
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Segregation distorters

Lyttle, TW,  Annual Review of Genetics,  25:511-557. 1991.
Segregation distorters are genetic elements that exhibit the phenomenon of meiotic drive; that is, the mechanics of the meiotic divisions cause one member of a pair of heterozygous alleles or heteromorphic chromosomes to be transmitted to progeny in excess of the expected ...
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Meiotic drive against an autosomal supernumerary segment promoted by the presence of a B-chromosome in females of the grasshopper Eyprepocnemis plorans

Lopezleon, MDC, J.; Camacho, J. P. M.,  Chromosoma,  100:282-287. 1991.
Twenty-seven out of 50 progeny analyses performed with specimens of the grasshopper Eyprepocnemis plorans were informative about the transmission of a supernumerary heterochromatic chromosome segment. The simultaneous presence of a B chromosome in some of the parents involved in ...
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B-chromosome drive

Jones, RN,  American Naturalist,  137:430-442. 1991.
The view of B-chromosome polymorphisms that is coming into favor resembles the so-called "parasitic" model, which was first advanced 45 yr ago. Since that time, repeated and ongoing efforts have been made to ascribe an adaptive role to B's (e.g., in terms of phenotypic advantage, ...
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Genetics-driving genes and chromosomes

Charlesworth, B,  Nature,  332:394-395. 1988.
Thereare several genetic and chromosomal systems in which Mendel's first law - the equal probability of transmission of maternal and paternal alternative alleles or homologues - is violated. This phenomenon was named 'meiotic drive' in 1957 by Sandler and Novitski, who drew ...
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Control of meiotic drive of B-chromosomes in the mealybug, Pseudococcus affinis (obscurus)

Nur, UB, B. L. H.,  Genetics,  115:499-510. 1987.
Isofemale lines of Pseudococcus affznis (MASKELL) differ in their ability to maintain B chromosomes (Bs) due to the presence of genotypes that affect the rate of transmission (k) of the Bs. The nature of these genotypes was analyzed by comparing ks of males carrying the same B ...
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Tthe genetic control of meiotic drive acting on the B-chromosome of Myrmeleotettix maculatus (Orthoptera, Aacrididae)

Shaw, MWH, G. M.,  Heredity,  54:187-194. 1985.
Crosses between populations with and without B-chromosomes were made, and backcrossed to the non B parent for two generations. No polygenic differences in male or female meiotic transmission were found, but a modifier of meiotic drive segregated in the experiment, drastically ...
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Polymorphism in the rates of meiotic drive acting on the B-chromosome of Myrmeleotettix maculatus

Shaw, MWH, G. M.; Anderson, D. A.,  Heredity,  55:61-68. 1985.
A survey of all the available data on meiotic transmission rates in M. maculatus suggests that a polymorphism in female transmission rate exists in most natural populations. Differences in the frequency of the types or in the transmission rates they manifest may exist between ...
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Genotypes suppressing meiotic drive of a B-chromosome in the mealybug, Pseudococcus obscurus

Nur, UB, B. L. H.,  Genetics,  110:73-92. 1985.
The rate of transmission (k) of a supernumerary B chromosome in male mealybugs is shown tq depend strongly on the chromosome set of materpal origin. When both parents came from an isofemale line in which the frequency of the B chromosome increased rapidly and stabilized at a mean ...
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Meiotic drive for B-chromosomes in primary oocytes of Myrmeleotettix maculatus (Orthoptera-Acrididae)

Hewitt, GM,  Chromosoma,  56:381-391. 1976.
Using a modified technique which allowed observation of chromosome orientation in the primary oocyte of grasshoppers at the onset of anaphase, it has been possible to establish that the B-chromosome is distributed preferentially on the egg side of the metaphase plate rather than ...
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Parasitic nature of extra fragment chromosomes

Östergren G.,  Botaniska Notiser,  2:157-163. 1945.
This paper is intended as a contribution to the discussion con­cerning the significance of the extra fragments or »accessory chromo­somes» as they are called by Håk ansso n(1945), which are not too rarely found in cross-fertilizing populations. I think reasonable support may ...
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