Comparative feline genomics: A BAC/PAC contig map of the major histocompatibility complex class II region

The genome organization of the human major histocompatibility complex (MHC) will be best understood in a comparative evolutionary context. We describe here the construction of a physical map for the feline MHC. A large-insert domestic cat genomic DNA library was developed using a P1 artificial chrom osome (PAC) with a genomic representation of 2.5 x and an average insert si ze of 80 kb. A sequence-ready 660-kb bacterial artificial chromosome/PAC co ntig map of the domestic cat MHC class II region was constructed with a gen e order similar to, but distinct from, that of human and mice: DPB/DPA, Rin g3, DMB, TAP1, DOB, DRB2, DRA3, DRB1, DRA2, and DRA1. Fluorescence in situ hybridization analyses of selected class II PAC clones confirmed that the c lass II region lies in the pericentromeric region of cat chromosome B2. How ever, apparently unlike the human and mouse MHCs, the domestic cat DRA and DRB genes have undergone multiple duplications and the DQ region has been d eleted. (C) 2001 Academic Press.