New recombinant HLA-B alleles in a tribe of South American Amerindians indicate rapid evolution of MHC class I loci.
Watkins DI,
McAdam SN,
Liu X,
Strang CR,
Milford EL,
Levine CG,
Garber TL,
Dogon AL,
Lord CI,
Ghim SH, et al.
Harvard Medical School, New England Regional Primate Research Center, Southborough, Massachusetts 01772.
Evidence suggests that the New World was colonized only 11,000-40,000 years ago by Palaeo-Indians. The descendants of these Palaeo-Indians therefore provide a unique opportunity to study the effects of selection on major histocompatibility complex class I genes over a short period. Here we analyse the class I alleles of the Waorani of South America and the Zuni of North America. Four of the Waorani HLA-B alleles were new functional variants which could be accounted for by intralocus recombination. In contrast, all of the Zuni HLA-A and -B molecules were present in caucasians and orientals. This suggests that the new Waorani HLA-B variants arose in South America. The description of four new HLA-B alleles in the Waorani and another five new HLA-B alleles from two other tribes of South American Amerindians indicates that the HLA-B locus can evolve rapidly in isolated populations. These studies underline the importance of gathering genetic data on endangered native human populations.
PMID: 1589035 [PubMed - indexed for MEDLINE]