Abstract: | The highly polymorphic locus D2S3 is revealed by three single-copy probes from cosmid C1-5. These probes, 1-30, 1-32, and 2-96, collectively reveal seven restriction fragment length polymorphisms. Fifty-three of 56 unrelated individuals (93%) were heterozygous at one or more of the seven loci, making the compound locus a very useful marker for gene mapping. Chromosomal assignment of D2S3 was obtained using a panel of human X hamster and human X mouse somatic cell hybrids. Molecular hybridization of EcoRI-digested DNA from these cell lines with the DNA inserts from subclones 1-30, 1-32, and 2-96 showed that all three probes mapped to the long arm of chromosome 2. Additionally, in situ hybridization of 3H]-labeled probe 2-96 to metaphase chromosome preparations allowed more precise assignment of the locus to the region 2q35----37. |