A GENETIC-MAP OF THE MOUSE WITH 4,006 SIMPLE SEQUENCE LENGTH POLYMORPHISMS

We have constructed a genetic map of the mouse genome containing 4,006 simple sequence length polymorphims (SSLPs). The map provides an aver age spacing of 0.35 centiMorgans (cM) between markers, corresponding t o about 750 kb. Approximately 90% of the genome lies within 1.1 cM of a marker and 99% lies within 2.2 cM. The markers have an average polym orphism rate of 50% in crosses between laboratory strains. The markers are distributed in a relatively uniform fashion across the genome, al though some deviations from randomness can be detected. In particular, there is a significant underrepresentation of markers on the X chromo some. This map represents the two-thirds point toward our goal of deve loping a mouse genetic map containing 6,000 SSLPs.