The fickle Y chromosome

Abstract

[...] those analyses excluded the Y chromosome, much of the genetic sequence of which is made up of palindromes and elaborate mirrored sets of bases that elude standard whole-genome sequencing techniques. The Y chromosome is also prone to change because most of its characterized genes are involved in producing sperm, which are at the frontline of reproductive fitness, particularly in chimps; receptive females will often mate with many males in one session, so the male with the most virile sperm has the highest likelihood of success.