[Analysis of HLA-Cw, KIR2D genetic variations in 2 Chinese populations].
OBJECTIVE
To explore the genetic variations of HLA-Cw and 5 KIR2D loci in 2 Chinese Han populations residing at Southern and Northern mainland China, respectively, and to investigate the HLA-Cw polymorphism of a Mongolian Chinese population.


METHODS
HLA-Cw genotyping was performed in a total of 293 healthy individuals including 1 Southern Han population living in Hunan Province (n=112), 1 Northern Han population (n=98) and 1 Mongolian Chinese population(n=83) in the Inner Mongolia Autonomous Region, using polymerase chain reaction-sequence specific primer(PCR-SSP) technique. Dimorphism at residue 80 of domain in the HLA-Cw molecule was examined by an additional set of PCR-SSP reactions. PCR-SSP was also used to detect the presence or absence of inhibitory KIR2DL1/2DL2/2DL3 loci and activating KIR2DS1/2DS2 loci for the 2 Han populations.


RESULTS
The main findings were: (1) Very significant frequency difference in the HLA-Cw alleles and dimorphism at codon 80 was detected between Hunan Han and Northern Han population, and between Hunan Han and Mongolian population (P < 0.001),while there was no such difference between the 2 Northern Chinese populations (P> 0.05); (2) There was no significant difference in frequencies of either the 5 individual KIR2D genes or the genotype distributions between the 2 Han populations (P> 0.05); (3) Asn(80)ls/Asn(80), 2DL1+/2DL2-/2DL3+/2DS1-/2DS2- predominated in both Han populations (45/112, 29/98), followed by Asn(80)/Asn(80), 2DL1+/2DL2-/2DL3+/2DS1+/2DS2- (18/112,16/98) and Asn(80)/Lys(80), 2DL1+/2DL2-/2DL3+/2DS1-/2DS2-(11/112,17/98). Among the 12 types of HLA-Cw codon 80 and KIR2D combinations, only Lys(80)/Lys(80), 2DL1+/2DL2-/2DL3+/2DS1-/2DS2- showed marginally significant frequency difference between the 2 Han populations(1/112 vs 8/98; Fisheros P was 0.0134).


CONCLUSIONS
Our study provided the polymorphism data of HLA-Cw gene for 3 Chinese populations with different geographic and/or ethnic background, we further analyzed the distribution of 5 KIR2D receptor genes in 2 Han populations. Our data suggest that in spite of HLA-Cw heterogeneity, remarkable similarities may exist between the Southern and Northern Chinese Han populations at the combinational level of HLA-Cw and KIR2D, which are characterized by preponderant inhibitory signal pathways.
Cai
Jin-hong
JH
Department of Immunology, College of Basic Medical Sciences, Central South University, Changsha, Hunan, 410013 People's Republic of China.
Tian
Wei
W
Li
Li-xin
LX
Wang
Fan
F
Sun
Ke-zhu
KZ
Zeng
Qing-ren
QR
Guo
Shi-shi
SS
Cao
Ya
Y
D044466:Asian People; D014644:Genetic Variation / Q000235:genetics*; D015236:HLA-C Antigens / Q000235:genetics*; D006801:Humans; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D054340:Receptors, KIR / Q000235:genetics*; D054342:Receptors, KIR2DL1 / Q000235:genetics; D054343:Receptors, KIR2DL2 / Q000235:genetics; D054344:Receptors, KIR2DL3 / Q000235:genetics
D015236:HLA-C Antigens; C093100:KIR2DL1 protein, human; C515077:KIR2DL2 protein, human; C515078:KIR2DL3 protein, human; C496212:KIR2DS1 protein, human; C433932:KIR2DS2 protein, human; D054340:Receptors, KIR; D054342:Receptors, KIR2DL1; D054343:Receptors, KIR2DL2; D054344:Receptors, KIR2DL3