Genetic differences between chimpanzees and people are more complicated than scientists had previously suspected, according to an international team.
Asao Fujiyama of the National Institute of Informatics in Tokyo and his colleagues used genetic material from three adult chimps to determine the entire DNA sequence of the animals' chromosome 22. They compared this chimp-chromosome sequence with previously acquired sequence data for its counterpart in people, chromosome 21.
As expected, the sequences, which consist of tens of millions of genetic letters, differ at only about 1.44 percent of those letters, or nucleotides. Surprisingly, though, nearly 68,000 stretches of DNA do differ to some degree between the two species, the researchers report in the May 27 Nature