HLA-A-ASTERISK-8001 IS A MEMBER OF A NEWLY DISCOVERED ANCIENT FAMILY OF HLA-A ALLELES

A member of a new HLA-A locus family, HLA-A8001, has been characteriz ed from 3 African-American individuals expressing a unique HLA-A serol ogic specificity. The HLA-A8001 sequence is most closely related to a lleles of the HLA-A1/3/11 family, although it also contains residues c haracteristic of the HLA-A2/28, -A9, -A10, and -A19 families. More imp ortantly, the HLA-A8001 sequence contains four unique nonsynonymous ( amino acid replacing) nucleotide substitutions absent from all other p rimate A locus alleles. In addition, five other nucleotide substitutio ns, four nonsynonymous and one synonymous (silent), observed only in n on-human primate A locus alleles were found. Neighbor-joining tree ana lysis of HLA-A8001 supports the notion that the HLA-A*8001 allele is a member of a new HLA-A locus family which was derived from the ancest ral A3 lineage but diverged early in the evolution of the HLA-A locus.