HLA cosmid clones show complete, widely spaced human class I genes with occasional clusters

To understand the organization of the human leukocyte antigen (HLA) gene region and its relationship to the transplantation antigens expressed at the cell surface we have isolated clones containing HLA class I genes from a cosmid library (Grosveld et al., Gene 13, 227, 1981) constructed with the DNA from an individual of defined haplotype. Most of the cosmids contain a single HLA gene in 30-40 kb of human DNA, indicating that human class I genes are rather widely spaced; two contain two genes and one contains three. Most of these genes appear to be complete; the double or multiple genes are found in the same orientation. Differences in restriction maps are evident but some common features are observed in particular in the 5' half of these genes.