Evolution of Genomic Structures on Mammalian Sex Chromosomes

Author(s): Yukako Katsura, Mineyo Iwase, Yoko Satta .

Journal Name: Current Genomics

Volume 13 , Issue 2 , 2012

Become EABM
Become Reviewer

Abstract:

Throughout mammalian evolution, recombination between the two sex chromosomes was suppressed in a stepwise manner. It is thought that the suppression of recombination led to an accumulation of deleterious mutations and frequent genomic rearrangements on the Y chromosome. In this article, we review three evolutionary aspects related to genomic rearrangements and structures, such as inverted repeats (IRs) and palindromes (PDs), on the mammalian sex chromosomes. First, we describe the stepwise manner in which recombination between the X and Y chromosomes was suppressed in placental mammals and discuss a genomic rearrangement that might have led to the formation of present pseudoautosomal boundaries (PAB). Second, we describe ectopic gene conversion between the X and Y chromosomes, and propose possible molecular causes. Third, we focus on the evolutionary mode and timing of PD formation on the X and Y chromosomes. The sequence of the chimpanzee Y chromosome was recently published by two groups. Both groups suggest that rapid evolution of genomic structure occurred on the Y chromosome. Our re-analysis of the sequences confirmed the species-specific mode of human and chimpanzee Y chromosomal evolution. Finally, we present a general outlook regarding the rapid evolution of mammalian sex chromosomes.

Keywords: Ectopic gene conversion, evolutionary strata, inverted repeats, palindrames, recombination suppression, sex chromosomes, Kallmann syndrome, pseudogene, nucleotide divergence, duplication

Rights & PermissionsPrintExport Cite as

Article Details

VOLUME: 13
ISSUE: 2
Year: 2012
Page: [115 - 123]
Pages: 9
DOI: 10.2174/138920212799860625

Article Metrics

PDF: 12