A PANEL OF RADIATION HYBRIDS AND YAC CLONES SPECIFIC FOR HUMAN-CHROMOSOME-5

We report the characterization, by reverse fluorescence in situ hybrid ization (FISH), of 59 hybrids retaining fragments of human chromosome 5. Most of these hybrids are radiation hybrids generated by gamma irra diating, at low dosage, a monochromosomal hybrid retaining chromosome 5 as its only human contribution. The partial chromosome paints genera ted from these hybrids will make powerful tools for cytogenetic invest igations, especially on the cytogenetic evolution of primates, and exa mples are reported. The molecular characterization of these hybrids wa s refined using 74 sequence-tagged sites (STSs), which allowed the phy sical dissection of chromosome 5 into 71 distinct regions with an aver age length of 2.7 Mb. The panel, therefore, is also suitable for high- precision subregional mapping of new genes or sequences located on chr omosome 5. As an additional resource for cytogenetic studies involving chromosome 5, we report the characterization, by FISH, of 73 YACs fro m CEPH. The vast majority of these YACs are recognized by at least one of the STSs used for hybrid characterization, thus enabling the integ rated use of YACs and partial chromosome paints derived from the hybri ds.