Characterization of Killer cell immunoglobulin‐like receptor (KIR) genotypes and haplotypes in Chinese Han population

Abstract

We performed Killer cell immunoglobulin-like receptor (KIR) genotyping on 1271 individuals of Chinese Han origin including 102 families and 965 unrelated individuals. The families (with one child and both parents) were subjected for haplotype analysis. Forty-one different genotypes were identified. The frequencies of the KIR genotypes found in the family panel were confirmed by those found in the unrelated panel. The family study showed segregation of one A haplotype and at least 15 unique B haplotypes. The most commonly observed haplotypes in group B were B1, B2, and B3, present at a frequency of 10.05%, 6.62%, and 4.90%, respectively. On the basis of the combination of KIR genes, six centromeric and seven telomeric gene motifs have been identified. Motif cB02 was the most frequent haplotype B specific centromeric segment while tB01 was the most frequent haplotype B specific telomeric segment. The distinct distribution of KIR haplotypes in each population may reflect the history of directional and balancing selection of different races. The gene combinations of group A and B1/B2/B3 haplotype were the most frequent genotypes named as Bx1, Bx2, and Bx3, present at a frequency of 13.72%, 7.35%, and 4.41% in the family panel, and at a frequency of 15.86%, 10.15%, and 5.80% in the unrelated panel, respectively. Overall, this study showed the diversity of KIR haplotypes and genotypes in Chinese Han population and developed a criterion for distinguish KIR haplotypes/genotypes for the population. KIR genotyping and haplotype analysis should be useful for selection of the most optimum donor grafts with favorable KIR gene content for transplants.

Population‐specific criterion to distinguish killer cell immunoglobulin‐like receptor genotypes and haplotypes in a large Eastern Han population

“…The order was adjusted due to the expansion of the sample cohort. For example, the most common B1 haplotype published in 2013 was still described as KH‐C‐001B, but the haplotype B14, which had previously been found to be not so common, was defined as KH‐C‐005B due to the increase in its haplotype frequency.…”

“…K. Jiang et al reported putative KIR haplotypes from unrelated individuals in 2005 . We then analyzed KIR haplotypes using a segregation study on families of Chinese Han origin …”

“…16 We then analyzed KIR haplotypes using a segregation study on families of Chinese Han origin. 17 The goal of the present study is to complement the KIR gene and haplotype data on Eastern Han by studying a large population and to improve the population-specific criteria to distinguish between KIR haplotypes in the region. This will facilitate donor searches by determining the possible haplotypes and/or gene motifs and may offer a research direction for further gene functional studies.…”

Donor Killer Immunoglobulin-Like Receptor Profile Bx1 Imparts a Negative Effect and Centromeric B-Specific Gene Motifs Render a Positive Effect on Standard-Risk Acute Myeloid Leukemia/Myelodysplastic Syndrome Patient Survival after Unrelated Donor Hematopoietic Stem Cell Transplantation

“…All patients (n=210) were assigned into two groups depending on the presence or absence of HLA Chinese population from our previous family study (19). One haplotype with unique Cen-and Telmotifs was excluded since it was only observed in one family and the same profile was not detected in the present study.…”

“…Because 5 Cen KIR gene motifs and 6 Tel KIR gene motifs were identified in Chinese population by our previous family study (19), haplotypes of the Cen-and Tel-parts of the KIR locus in Chinese Han were assigned as defined. The gene content of the identified motifs is shown in Because 2DL3 can only be identified in the centromere of the A haplotype, Cen-A/B was defined as harboring 2DL3 and at least one B-haplotype-defining KIRs (2DL2, 2DL5B, and 2DS2).…”