Natural killer cell immunoglobulin-like receptor (KIR) locus profiles in African and South Asian populations.
Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations.
Norman
P J
PJ
South Thames Tissue Typing, Guy's Hospital, London, UK. paul.norman@kcl.ac.uk
Carrington
C V F
CV
Byng
M
M
Maxwell
L D
LD
Curran
M D
MD
Stephens
H A F
HA
Chandanayingyong
D
D
Verity
D H
DH
Hameed
K
K
Ramdath
D D
DD
Vaughan
R W
RW
D000354:Africa, Western; D001459:Bangladesh; D005787:Gene Frequency; D006239:Haplotypes; D006801:Humans; D007194:India; D007694:Killer Cells, Natural / Q000276:immunology; D015810:Linkage Disequilibrium; D010154:Pakistan; D011971:Receptors, Immunologic / Q000235:genetics*; D054340:Receptors, KIR; D054345:Receptors, KIR2DL4; D014300:Trinidad and Tobago / Q000208:ethnology
D011971:Receptors, Immunologic; D054340:Receptors, KIR; D054345:Receptors, KIR2DL4