BLOCK-based PCR markers to find gene family members in human and comparative genome analysis

Degenerate primer pairs that include consensus sequences of evolutionary conserved portions of protein families (BLOCKs or ancient conserved regions) can be used to screen by polymerase chain reaction (PCR) for cognate cDNAs and YACs through much of phylogeny. Nine such primer pairs were developed, and five with sites on human chromosomes 7 or X were shown to identify YACs from chromosome-specific locations, including a candidate for a new zinc finger gene in Xq28. When linked to contig-based genomic maps, such BLOCK-based PCR assays may provide a route to recover the members and study the development of families containing up to 40% of genes, in genomes as diverse as humans, nematodes, and yeast.