Kir Haplotypes Defined By Family Analysis In Sichuan Han And Yi Families

Objective:To determine the gene content of the KIR haplotypes in Sichuan Hanand Yi families.Methods:82mouth swab samples from21Han families and384blood samplesfrom89Yi families were collected. The genomic DNA was extracted and genotypingwas done for16KIR loci by multiplex PCR-SSP (sequence-specific priming).Additionally, subtyping was carried out for3DP1and2DS4. KIR haplotypes werededuced according to KIR genotype combined with family analysis. When the copynumber could not be determined for certain samples, both qPCR (quantitative PCR) andfamily analysis were done to obtain their KIR haplotypes.Results: A total of13genotypes and12unique haplotypes were identified in Hanfamilies, including2A haplotypes and10B haplotypes. In Sichuan Han families,genotypes1,3，4and5contained3combinations of haplotypes; genotypes2,8and68contained2combinations of haplotypes; genotypes6,7,9，69，72and79contained1combination of haplotypes, respectively. A total of22genotypes and21haplotypes wereidentified in Yi families, including3A haplotypes and18B haplotypes. The ways ofhaplotypes combinations were shown as follows: genotypes3,4and5contained5combinations; genotypes1，7and68contained4combinations; genotypes6，9，70and188contained3combinations; genotypes2and8contained2combinations, respectively;the rest contained only one combination. The Han families and the Yi families share12genotypes and9haplotypes. For most genotypes there are several kinds of haplotypecombinations, even the same genotypes there are still different combinations ofhaplotypes between the Han families and the Yi families. Two unique haplotyes wereidentified in the Yi families. One was B haplotype lacking structural gene3DP1, whilethe other one was variational A haplotype containing3DPlv. In terms of the genomestructure in these heplotypes, except for the one lacking3DP1，the rests’ centromericterminals were comprised of KIR3DL3,2DS2,2DL2,2DL3,2DP1,2DL1and3DP1，which formed4major models:3DL3-2DL3-2DP1-2DL1-3DP1,3DL3-2DS2-2DL2-3DP1v,3DL3-2DL3-3DP1v,3DL3-2DS2-2DL2-2DP1-2DL1-3DP1. Nevertheless, the telomeric terminals contained multiple combinations of various activating KIR genes and possessed more structural models.Conclusions:Through the segregation analysis in the family studies, we found that the KIR haplotypes of Sichuan Han and Yi families had difference not only in the aspect of types, but also in the aspect of combinations even under the same KIR genotype. Thus, it was more precise to use KIR haplotype data obtained from Sichuan family analysis to deduce its distribution in Sichuan populations. We have shown that the Sichuan Han and Yi families shared the following characteristics:1) the pseudogene3DP1,2DP1and KIR2DL1showed up concurrently;2) the presence of KIR2DS1was associated with absence of KIR2DS4, and vice versa;3) KIR2DS2and KIR2DL2appeared concurrently. qPCR could be used to determine the copy numbers of KIR gene, and it was a helpful supplementary tool for certain KIR haplotype analysis. Objective:To analyze the gene frequency of killer cell immunoglobulin-like receptors(KIR) and the KIR/HLA combinations in the Sichuan Han population, to study the relationship between KIR and HLA.Methods:286unrelated individuals were randomly selected from CMDP Sichuan branch.16locus of KIR genotyped by PCR-SSP, HLA-A、HLA-B and HLA-C locus genotyped by PCR-SBT.Results:Among the Sichuan Han population, the frame locus:3DL2、3DL3、2DL4、3DP1have found in all individuals; a total of29kinds of KIR genotype were identified,in which the genotypes named ID1and ID2are most common genotypes, the frequency is47.55%(136/286) and14.69%(42/286).The frequencies of HLA-C1and HLA-C2are85.15%(487/572) and14.85%(85/572),the frequencies of HLA-B Bw4and HLA-A Bw4are31.99%(183/572) and20.78%(119/572). All individuals displayed at least one inhibitory KIR/HLA-C pair, the frequency of one KIR/HLA-C pair is found highest (77.27%),the two pairs is secondary(15.04%),followed the there pairs(7.69%).About the KIR/HLA-Bw4pairs, contain only3DL1+HLA-Bw4showed highest frequency (44.76%) and contain only3DS1+HLA-Bw4showed lowest frequency (2.80%), the frequency of who have both3DL1+HLA-Bw4and3DS1+HLA-Bw4is25.17%(72/286),27.27%(78/286) individuals in this population have no KIR/HLA-Bw4pair.Conclusions:Sichuan Han population possesses its unique features on the distribution of KIR genes and the main KIR/HLA pairs, inhibitory KIR/HLA pairs were predominant receptor/ligand pair.