It has been shown that selective pressure to compensate for the silencing of the sex chromosomes during male meiosis resulted in many X-linked genes being duplicated as functional retrogenes on autosomes. The silencing of male sex chromosomes was probably stratified during evolution, in accordance with their stratified diversification. Here I show that the timing of the retrocopying events is associated with the timing of the X-Y differentiation of the region of the X chromosome housing the parental copy of the gene.
Animals Evolution, Molecular