July 24, 2003
Male Female Differences
Nature 423, 825 - 837 (19 June 2003); doi:10.1038/nature01722
The male-specific region of the human Y chromosome is a mosaic of discrete sequence classes
HELEN SKALETSKY et al.
"Genetic and biological differences between males and females It is commonly stated that the genomes of two randomly selected members of our species exhibit 99.9% nucleotide identity. In reality, this statement holds only if one is comparing two males, or two females. If one compares a female with a male, the second X chromosome (160 Mb, or roughly 3% of the diploid DNA content) is replaced by the largely dissimilar Y chromosome (60 Mb, or 1% of the diploid DNA content). This common substitution of the Y chromosome for the second X chromosome dwarfs all other DNA polymorphism in the human genome. In decades past, and with the important exception of X-linked recessive diseases, biologists often judged this genomic dimorphism to be of limited functional consequence, especially because of inactivation of the second X chromosome in females and the presumed paucity of genes in the Y chromosome. Now we must begin to reconsider this position, given the unanticipated number and variety of MSY genes, many of which are expressed throughout the body, and the fact that many X-linked genes are expressed from both X chromosomes in female cells47. The present sequence of the MSY, and the emerging sequence of the X chromosome, offer the near prospect of a comprehensive catalogue of genetic and sequence differences between human males and females. Translating this knowledge into an understanding of the myriad differences between the sexes in anatomy, physiology, cognition, behaviour and disease susceptibility presents a monumental challenge, but surely one of broad significance and interest."
Posted by Dienekes at July 24, 2003 09:24 PM | PermaLink