AN INTEGRATED YAC MAP OF THE HUMAN X-CHROMOSOME

The human X chromosome is associated with a large number of disease ph enotypes, principally because of its unique mode of inheritance that t ends to reveal all recessive disorders in males. With the longer term goal of identifying and characterizing most of these genes, we have ad opted a chromosome-wide strategy to establish a YAC contig map. We hav e performed >3250 inter Alu-PCR product hybridizations to identify ove rlaps between YAC clones. Positional information associated with many of these YAC clones has been derived from our Reference Library Databa se and a variety of other public sources. We have constructed a YAC co ntig map of the X chromosome covering 125 Mb of DNA in 25 contigs and containing 906 YAC clones. These contigs have been verified extensivel y by FISH and by gel and hybridization fingerprinting techniques. This independently derived map exceeds the coverage of recently reported X chromosome maps built as part of whole-genome YAC maps.