KIR gene diversity in Mexican mestizos of San Luis Potosí

Abstract

Natural killer (NK) cell function is regulated by different types of membrane-bound receptors of which killer-cell immunoglobulin-like receptors (KIRs) are the most complex and diverse. KIRs are encoded by 17 different genes located within the leukocyte receptor complex (19q13.4). The frequency with which KIR gene features are present in different human populations differs. Here, we present our results on the KIR gene diversity observed in a large group of mestizos from the central Mexican city of San Luis Potosí. In total, 53 different KIR genotypes were observed, 47 with previously described gene profiles and six harboring novel KIR gene combinations. Group A homozygous haplotypes were seen in 102 individuals (34%), while group B homozygous haplotypes were present in 45 (15%). Heterozygous combinations of groups A and B haplotypes were seen in 153 individuals (51%). Haplotype frequency estimations based on a true content of 600 chromosomes showed a relatively balanced proportion of group A (59.5%) and group B (40.5%) haplotypes in our study population. A homozygous combination of the cA01|tA01 haplotype was present in 33% of the population with other frequent combinations being cA01|tA01, cB03|tB01 in 14.7% and cA01|tA01, cB02|tA01 in 12%. The dendrogram derived from activating KIR gene phylogenetic analysis revealed five clearly distinct clades corresponding to African, East Asian, Arab/Caucasoid, Mexican mestizo/Amerindian and South Asian populations. Our results illustrate the genetic contribution that Caucasoid and Amerindian populations have made toward present-day Mexicans and suggest an important Southeast Asian genetic contribution to native Amerindian populations.

Diversity of killer cell immunoglobulin like receptor genes in the Mongolian population

“…Alvarado has analyzed 60 human populations phylogeny based on activating KIR gene frequencies. All populations have been clustered to six clades: East Asian, Arab/Caucasoid, Mexican mestizo/Amerindian and South Asian, African [29]. In our PCA results, East Asian and Caucasoid also clustered respectively, whereas Mongolian was not gathered to neither East Asian nor Caucasoid populations, has similar genetic distances to east Asian or Caucasoid clades in genetic trees.…”

NKG2C gene deletion in the Mexican population and lack of association to respiratory viral infections

“…The frequency of the NKG2C deletion in our population was assessed with the use of DNA samples belonging to the Mexican Reference Genomic DNA Collection (MGDC‐REF) which is composed of 300 healthy donors (Alvarado‐Hernández et al ., ). For the case–control association study, patients with virologically confirmed respiratory syncytial virus (RSV) ( n = 61), and pandemic A (H1N1) 2009 influenza ( n = 70) infections were included.…”

Association of KIR3DL1/S1 and HLA-Bw4 with CD4 T cell counts in HIV-infected Mexican mestizos

“…KIR, HLA-B public epitope typing and broad HLA-C group 1 or 2 typing were performed using previously published SSP-PCR-based strategies (Alvarado-Hernandez et al 2011;Bunce et al 1995;Hiby et al 2008). Our KIR genotyping approach does not discriminate between KIR2DL5A and 2DL5B or the centromeric or telomeric localization of KIR2DS3, 2DS5 and 2DL5A/B.…”

“…This admixture occurred soon after the Spanish conquest of 1521 and has also been influenced, to a lesser extent, by recent human migrations (Alvarado-de la Barrera et al 2000). KIR and HLA traits in Mexican mestizos have been shown to be different from those present in other human groups (Alvarado-Hernandez et al 2011;Contreras et al 2007;Vargas-Alarcon et al 2010). More importantly, the distribution of Bw4-bearing HLA-B alleles in the Mexican mestizo population is different to that of Caucasoids, see Table 1.…”