Microsatellite typing of the rhesus macaque MHC region

Abstract

To improve the results gained by serotyping rhesus macaque major histocompatibility complex (MHC) antigens, molecular typing techniques have been established for class I and II genes. Like the rhesus macaque Mamu-DRB loci, the Mamu-A and -B are not only polymorphic but also polygenic. As a consequence, sequence-based typing of these genes is time-consuming. Therefore, eight MHC-linked microsatellites, or short tandem repeats (STRs), were evaluated for their use in haplotype characterization. Polymorphism analyses in rhesus macaques of Indian and Chinese origin showed high STR allelic diversity in both populations but different patterns of allele frequency distribution between the groups. Pedigree data for class I and II loci and the eight STRs allowed us to determine extended MHC haplotypes in rhesus macaque breeding groups. STR sequencing and comparisons with the complete rhesus macaque MHC genomic map allowed the exact positioning of the markers. Strong linkage disequilibria were observed between Mamu-DR and -DQ loci and adjacent STRs. Microsatellite typing provides an efficient, robust, and quick method of genotyping and deriving MHC haplotypes for rhesus macaques regardless of their geographical origin. The incorporation of MHC-linked STRs into routine genetic tests will contribute to efforts to improve the genetic characterization of the rhesus macaque for biomedical research and can provide comparative information about the evolution of the MHC region.

Simian Immunodeficiency Virus SIVmac239 Infection of Major Histocompatibility Complex-Identical Cynomolgus Macaques from Mauritius

“…Multiplex PCR assays were developed for 18 microsatellite loci spanning the MHC region (Table 1). Four of these loci were adapted for cynomolgus macaques from a previous study with rhesus macaques (31). Additional microsatellites were identified by screening human MHC primer pairs (15) for specificity against the rhesus MHC genomic sequence (9) with BLASTn (2).…”

“…1). The majority of the primers used to amplify these markers were adapted to reflect rhesus genomic sequences (Table 1) (9,15,31). First, we used these markers to genotype DNA from five MCM previously shown to possess the MHC class I alleles Mafa-B*430101, Mafa-B*440101, and Mafa-B*460101 (20).…”

“…To verify that the microsatellite haplotype signatures associate with discrete MHC class II genotypes, we examined the highly polymorphic MHC class II-DRB locus (4,23,31). We used allele-specific PCR with representative homozygous MCM genomic DNAs to assign 11 of 15 known Mauritian DRB alleles to haplotypes H1 through H6 (Table 3).…”

“…Remarkably, both MHC-identical animals exhibited mutations in these regions, though the affected amino acids were distinct in each animal. With the exception of the Tat [26][27][28][29][30][31][32][33][34][35][36] region, strong CTL responses were detected at 3 weeks postinfection in at least one of the two animals (data not shown), strongly suggesting that the shared variability results from immune escape.…”

“…Unfortunately for SIV research, this diversity generally limits investigators to MHC matching animals for single class I alleles, such as Mamu-A*01, rather than entire MHC haplotypes (6,14). Shared MHC haplotypes, comprising MHC class IA and IB genes, MHC class II genes, and tightly linked genes involved in antigen processing and inflammation (16), have been identified only in rhesus macaques related by descent (31,42). Therefore, it is exceedingly difficult to study the influence of the entire gene-dense MHC region on SIV pathogenesis in unrelated rhesus macaques.…”