COMPARISON OF THE POSITIONAL CLONING METHODS USED TO ISOLATE THE BRCA1 GENE

A critical step in positional cloning is the identification of candida te genes from a large, genetically defined region, Candidate gene isol ation by hybrid selection, genomic sequencing, and direct cDNA library screening identified 45 candidate gene fragments (CGFs) from a 600 kb genomic region that contains the BRCA1 gene, These CGFs define a mini mum of 15 genes, six of which are newly localized to the BRCA1 region, We present an analysis of the efficiency and the sequences generated for each of these methods, We also compare our CGF set to those report ed for the BRCA1 region by three other groups, revealing a surprising lack of overlap among the sets.