The Mappers’ Torch Song
- The Human Genome Center, Department of Medicine, University of Washington, Seattle, Washington 98195 USA
This extract was created in the absence of an abstract.
Recently, after almost a decade of effort, two groups—one led by David Schlessinger at Washington University (Nagaraja et al. 1997), and another led by Eric Green at the National Human Genome Research Institute (Bouffard et al., this issue)—announced the completion of yeast artificial chromosome (YAC)-based sequence-tagged site (STS)-content physical maps for human chromosomes X and 7, respectively. Although we understand why most of the world is seeking alternatives to the many years of laborious work involved in building such maps, we feel that precisely because maps of such high quality are so rare, their completion should be celebrated. As these announcements signal the symbolic “passing of the torch” from mapping to sequencing, it is timely to reflect on what has been accomplished and on what lies ahead for the Human Genome Project (Watson 1990; Collins and Galas 1993).
A number of factors distinguish these two maps from others that have been published previously (Foote et al. 1992; Ashworth et al. 1995;Bell et al. 1995; Chumakov et al. 1995; Collins et al. 1995; Crollius et al. 1996; Doggett et al. 1995; Hudson et al. 1995; Krauter et al. 1995; Quackenbush et al. 1995; Qin et al. 1996): First, the significant size of chromosomes X and 7 is estimated at 160 and 170 Mb, respectively; the next largest chromosome-specific map, for chromosome 11, is 130 Mb. Second, the high density of STS markers on these maps averages 80 kb in both cases, which is better than the 100 kb goal set by the Human Genome Project …
