A Chimpanzee Genome Project Is a Biomedical Imperative

A near-complete sequence of the human genome is now available, and many efforts are currently focused on the next logical biomedically relevant target — the mouse genome. Given limited resources, which vertebrate genome(s) should be tackled after that? Reasonable candidates include other well-studied model organisms such as Rattus rattus (the rat), Xenopus laevis (the African clawed toad), and Danio rerio (the zebra fish). Over the last few years, some have been advocating a genomic approach toward understanding our closest evolutionary relatives, the great apes (McConkey and Goodman 1997; Paabo 1999;McConkey et al., 2000). Pan troglodytes (the chimpanzee) andPan paniscus (the bonobo) share nearly 99% of human genomic sequences (see Box for discussion) (King and Wilson 1975; Sibley and Ahlquist 1984; Caccone and Powell 1989; Ruvolo 1997; Goodman et al. 1998; Satta et al. 2000). Thus, it is cogently argued that knowing the complete genome of at least one of these species will give us a window into genes that contribute to humaness (the chimpanzee is the first choice, because we know more about this species than we do about the bonobo). The emergence of humans can be regarded as one of the major transitions in evolution (Szathmary and Smith 1995), and the complete explanation of this phenomenon ranks as one of the greatest unsolved mysteries of science.