Chimp genome mapped

with the recent release of a draft map of the chimpanzee genome, scientists hope to gain fresh understanding of human evolution since the human-chimp split roughly 6 million years ago.

Better conservation of male y chromosome in humans, expression of foxp2 gene -- involved in speech -- in humans and presence of a gene in the chimp genome that offers protection to the primate against Alzheimer's disease are some of the significant initial finds by the Chimpanzee Sequencing and Analysis Consortium (Nature, Vol 437, No 7055, September 1, 2005).

David Page of Whitehead Institute in Massachusetts says there were damaging genetic mutations in the y chromosome of chimpanzees as compared to humans. Scientists argue this could be because humans remained largely monogamous while chimpanzees have multiple sexual partners.

The dna of the common chimpanzee (Pan troglodytes) came from a male named Clint, who died last year at the Yerkes National Primate Research Center in Atlanta in the us.

If you take the most meaningful parts of the genome -- the genes that code the proteins that build and maintain cells -- are considered, the genetic sequences of human and chimpanzee differ by a mere 1 per cent. But, if the entire genome, including the poorly-understood parts, is taken into account, the difference becomes 96 per cent.

"Because the genomes are huge -- 3 billion base pairs of dna -- the differences in molecular terms are quite a lot," said genetic evolutionist Wen-Hsiung Li of Chicago University in an accompanying commentary in Nature. "Most of them probably will not be biologically significant, but some may be crucial. Our task now is to identify those that are meaningful and prove it in the laboratory."