Desafiando a Nomenklatura Científica: Cromossomo Y de chimpanzés e humanos: horrivelmente diferentes!!!

quinta-feira, maio 20, 2010

Published online 13 January 2010 | Nature 463, 149 (2010) | doi:10.1038/463149a

News

The fickle Y chromosome

Chimp genome reveals rapid rate of change.

Lizzie Buchen

The male sex chromosome, long dismissed as the underachieving runt of the genome, has now been fully sequenced in a common chimpanzee. And comparison with its human counterpart — the only other Y chromosome to have been sequenced in such detail — reveals a rate of change that puts the rest of the genome to shame.

His sex chromosome is an evolutionary hotspot.B. Walton/naturepl.com

The common chimp (Pan troglodytes) and human Y chromosomes are "horrendously different from each other", says David Page of the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, who led the work. "It looks like there's been a dramatic renovation or reinvention of the Y chromosome in the chimpanzee and human lineages."

Sex chromosomes evolved some 200 million–300 million years ago, but the chimpanzee and human lineages diverged only 6 million–7 million years ago. Comparisons of the chimp and human genomes suggested that not much has changed between the species since1.

But 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. Portions of the chimp Y chromosome were sequenced a few years ago2,3, but the full landscape is only now available, after Page and his team precisely sequenced large segments of the chromosome, then stitched them together. They report their findings in a paper published online in Nature on 13 January4.

...