Killer cell immunoglobulin-like receptor (KIR) genes and their HLA ligands in a Brazilian population

Abstract

Killer cell immunoglobulin-like receptors (KIR) exhibit extensive diversity, giving rise to different KIR profiles in populations worldwide. This study aimed to investigate the distribution of KIR genes and HLA ligands in a population from Campinas, southeastern Brazil (n = 292), and to compare their results with other populations. A comprehensive analysis of population-specific genes, genotype, and haplotype frequencies of KIR may facilitate a better understanding of their evolution and role in immunity. The genotyping of 16 KIR genes and HLA class I alleles was performed by the reverse sequence-specific oligonucleotide methodology using the Luminex platform (One Lambda, Inc., Canoga Park, CA). The framework genes were present in all individuals, with the most common non-framework KIR genes detected being KIR2DP1(96.6%), KIR2DL1(95.5%), KIR3DL1(94.5%), KIR2DS4(93.8%) and KIR2DL3(87.3%). KIR2DS1, KIR2DS3, KIR2DS5, and KIR3DS1 presented frequencies below 40%. KIR2DL2, KIR2DL5, and KIR2DS2 showed intermediate frequencies (between53% and 58%). The activating gene KIR2DS5 was the least common in this population (30.8%). Forty-five KIR profiles were found with the commonest being the homozygous A haplotype (27.4%). The distribution of KIR genes in the Brazilian population is similar to Caucasian European and Euro-descendant populations.

Unveiling the Significance of HLA and KIR Diversity in Underrepresented Populations

“…The researchers also observed a low prevalence of KIR haplotype A, constituting only 13% of the population, aligning with findings in other Central and South American populations [ 55 ]. In another study involving a Brazilian cohort [ 45 ], researchers observed KIR frequencies exceeding 90% for KIR2DL1 , KIR2DL3 , KIR3DL1 (inhibitory KIR), KIR3DS1 (activating KIR), and KIR2PD1 (pseudogene). These frequencies were compared with those in North, Central, and other South American populations, as well as Europe, Africa, Oceania, and Asia.…”