Next generation sequencing and the classical HLA loci in full heritage Pima Indians of Arizona: Defining the core HLA variation for North American Paleo-Indians.

The Pima Indians of the Gila River Indian Community in Arizona have participated in a long-range study of type 2 diabetes mellitus since 1965 and have been the subject of HLA typing and population studies since the early days of serological assays. These data have been in numerous HLA workshops and conferences and have been the source of at least five novel alleles at the classical HLA loci. In recent time nearly the entire study group was subject to next generation sequencing by whole genome or exome technologies, which has allowed us to HLA type over 3000 full heritage persons with recently developed computer algorithms. We present here the results for the classical HLA Loci: HLA-A, B, C, DRA, DRB1, DRB3, DRB4, DRB5, DPA1, DPB1, DQA1, and DQB1 to the third field of resolution for synonymous alleles and type the likely four field resolution alleles from the subset of whole genome sequences. Allele frequencies, and haplotype frequencies at up to five loci, are presented as well as measures of population structure and heterozygosity. We define a core set of HLA variation that approximates the distribution for the Paleo-Indians and impute nine-locus, 4-field haplotypes that are expected to be common in full heritage peoples.