This assumption derives from the fact that hybrid incompatibilities require functional evolutionary substitutions [ 6566 ], and natural selection fixes beneficial mutations much faster than drift will fix neutral or deleterious ones. Hybrid sterility is genetic conflict and sex chromosome evolution games in Gympie to the heterogametic sex due to the largely independent genetic control of meiosis and gametogenesis in the two sexes.
The nucleo-mitochondrial conflict in cytoplasmic male sterilities revisited. Reinke V, et al. Segregation distorters can arise on all chromosomes, but are particularly important in species with chromosomal sex determination for brevity, we will refer to the heterogametic sex as male and the sex chromosomes as X and Y, except where we explicitly compare XY and ZW systems.
The large X-effect has also been implicated from natural hybrid zones, as X-linked and Z-linked loci show steeper clines across hybrid zones than autosomal loci [ 7778 ]. Zeng ZB, et al.
Prowell DP. Sex-ratio distortion caused by meiotic drive in mosquitoes. Sex chromosomes and speciation in Drosophila. Whole genome transcription and sequencing studies have revealed that genes with elevated expression in male reproductive tissues relative to somatic or female reproductive tissues male-biased genes are under-represented on the X chromosome in mammals, fruit flies, and nematodes [ 36 - 39 ] with a possible exception in mosquitoes [ 40 ] ; female-biased genes are under-represented on the Z chromosome in birds [ 41 ].
Proc Biol Sci — M refers to meiosis, F to fertilization. Nevertheless, there are several cases of switch genes with no homologs in closely related taxa. Nat Rev Genet — Genesis — We then summarize the diversity of sex-determining mechanisms found among animals and plants and discuss the evolutionary forces that drive transitions among systems Myth 1 revisited.
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Presgraves DC. Solari AJ. The role of X-chromosome inactivation during spermatogenesis. Chromosome Res. Because such selfish elements on sex chromosomes can reduce fertility and distort the sex ratio of progeny, unlinked suppressors are expected to evolve, bringing different regions of the genome into conflict over the meiotic transmission of the sex chromosomes.