Gene Drive Strategy: Gonotaxis
When females produce eggs it involves meiosis, a cell division that halves the genome, and results often in 4 cells – 1 egg and 3 “polar bodies”. The polar bodies are cells much reduced in size relative to the egg that often will degenerate following their formation. In some organisms polar bodies may survive to contribute some reproductive functions but they are not functional eggs. The default patterns of inheritance result in chromosomes having a 50:50 chance of ending up in the egg and pole cells. But there are exceptions where one of a pair of chromosomes has more than a fair chance of ending up in an egg – a phenomenon known as gonotaxis or asymmetric meiosis. Chromosomes with those characteristics have a transmission advantage and display drive.
The short video (01:58) below graphically (no audio) illustrates the concepts.
This video (03:45) illustrates a proposed mechanism by which gonotaxis occurs based on studies in mice reported by Akera et al (2017).