KIR gene content diversity in four Iranian populations

Abstract

Killer cell immunoglobulin-like receptors (KIR) regulate natural killer cell response against infection and malignancy. KIR genes are variable in the number and type, thereby discriminating individuals and populations. Herein, we analyzed the KIR gene content diversity in four native populations of Iran. The KIR genomic diversity was comparable between Bakhtiari and Persian and displayed a balance of A and B KIR haplotypes, a trend reported in Caucasian and African populations. The KIR gene content profiles of Arab and Azeri were comparable and displayed a preponderance of B haplotypes, a scenario reported in the natives of America, India, and Australia. A majority of the B haplotype carriers of Azeri and Arab had a centromeric gene-cluster (KIR2DS2-2DL2-2DS3-2DL5). Remarkably, this cluster was totally absent from the American natives but occurred at highest frequencies in the natives of India and Australia in combination with another gene cluster at the telomeric region (KIR3DS1-2DL5-2DS5-2DS1). Therefore, despite having similar frequencies of B haplotypes, the occurrence of B haplotype-specific KIR genes, such as 2DL2, 2DL5, 3DS1, 2DS1, 2DS2, 2DS3, and 2DS5 in Azeri and Arab were substantially different from the natives of America, India, and Australia. In conclusion, each Iranian population exhibits distinct KIR gene content diversity, and the Indo-European KIR genetic signatures of the Iranians concur with geographic proximity, linguistic affinity, and human migrations.Electronic supplementary materialThe online version of this article (doi:10.1007/s00251-009-0378-7) contains supplementary material, which is available to authorized users.

The potential influence of KIR cluster profiles on disease patterns of Canadian Aboriginals and other indigenous peoples of the Americas

“…In addition, KIR2DL1, KIR2DL3, KIR2DS4 and KIR3DL1 genes within the A haplotype were present in over 84% of all individuals, a finding paralleled in other ethnic groups (Table 1; see Supplementary Table 1 for gf differences between Manitoban populations and details regarding the presence of KIR2DL5A and KIR2DL5B in these cohorts). [19][20][21][22] Conversely, marked variation was apparent in the genes associated with the B haplotype. Compared with Caucasian samples, the Aboriginal population exhibited a decreased presence of B haplotype centromeric genes KIR2DL2, KIR2DS2, as well as KIR2DS3 (Table 1).…”

Characterization of human killer immunoglobulin-like receptors (KIRs) among healthy Saudis

“…The B haplotype differ in its gene content, which is determined mainly by the presence or absence of the genes that are not part of the A haplotype. [5]. The framework KIR3DL2, -3DL3 and -2DL4 genes are present in both the A and B haplotypes, and most activating KIR genes are found within the B haplotype [8].…”

“…KIR genes are highly polymorphic and are located on chromosome 19q13.4 [5]. In humans, 16 KIR genes have been identified, defined as the KIR2DL1, -2DL2, -2DL3, -2DL4, -2DL5, -3DL1, -3DL2, -3DL3, -2DS1, -2DS2, -2DS3, -2DS4, -2DS5, -3DS1, -2DP1 and -3DP1 genes.…”

“…Full-length sequencing of KIR haplotypes showed that the framework regions divide the KIR locus into two parts: centromeric (C) and telomeric (T) segments that differ in their gene contents [5,9,10]. The centromeric part of the A haplotype contains KIR2DL3, -2DL1 and -2DP1, in addition to 3DL3 and -3DP1,while the telomeric part contains the KIR3DL1 and -2DS4 genes, in addition to KIR2DL4 and -3DL1.…”

Gene-Specific PCR Typing of Killer Cell Immunoglobulin-Like Receptors

“…On the basis of the presence and absence of C4 and T4 clusters, the Bx genotypes are further divided into the following four subsets: C4Tx (presence of C4 and absence of T4), CxT4 (absence of C4 and presence of T4), C4T4 (presence of both C4 and T4), CxTx (absence of both C4 and T4). These Bx subsets are substantially variable in activating KIR gene content, and their frequencies differ significantly between human populations [ 47 ].…”