Analysis of HLA-Cw, KIR2D genetic variations in 2 Chinese populations / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>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.</p>

Polymorphism of short tandem repeat of exon 5 of MHC class-I chain related gene A and association with nasopharyngeal carcinoma in a southern Chinese population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the association between the short tandem repeat polymorphism of exon 5 of MICA gene (MICA-STR) and nasopharyngeal carcinoma (NPC) in a southern Chinese population.</p><p><b>METHODS</b>One hundred and twenty-seven consecutive NPC patients and 112 randomly selected normal controls residing in southern China mainland were analyzed for MICA-STR allelic variation and MICA gene deletion by fluorescent polymerase chain reaction-gene scanning and polymerase chain reaction-sequence specific priming.</p><p><b>RESULTS</b>MICA*A9 was observed at significantly higher frequency in the NPC patient group than in the control group (relative risk = 2.524, P = 0.001,Pc = 0.006); whereas MICA*A5.1 was present at significantly lower frequency in the NPC patient group than in the control group (RR = 0.418, P = 0.0004, Pc = 0.0026). Further analysis revealed that MICA*A9 was over-represented in male NPC patients, compared with male controls (RR = 3.23, P = 0.00095, Pc = 0.006); whereas MICA*A5.1 was present at significantly lower frequency in male NPC patients, compared with male controls (RR = 0.372, P = 0.0007, Pc = 0.004). None of the MICA-STR variants showed statistically significant frequency difference between female NPC patients and female controls (Pc > 0.05).</p><p><b>CONCLUSION</b>MICA-STR polymorphism is associated with NPC, and MICA*A9 is a genetic susceptibility marker of male individuals for NPC in a southern Chinese population.</p>

Association study on HLA-DP and -DQ allelic polymorphisms and nasopharyngeal carcinoma in the Han nationality in Hunan province / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate whether the polymorphisms of HLA-DPA1,DPB1,DQA1 and DQB1 alleles were associated with nasopharyngeal carcinoma(NPC).</p><p><b>METHODS</b>Eighty-seven NPC patients and 91 normal controls of Han nationality in Hunan province were genotyped for HLA-DPA1, HLA-DPB1,HLA-DQA1 and HLA-DQB1 by PCR/SSO technique.</p><p><b>RESULTS</b>The frequencies of allelic gene DPA1*0201, DPB1*1901 and DQA1*0201 were lower, and of DPB1*0402, DQA1*0101 were higher in patients than in controls; the frequencies of haplotype DPA1*0201-DPB1*1401 and DQA1*0201-DQB1*0201 in patients were lower than those in controls; however, the values of P are not significant after Bonferroni correction(Pc>0.05).</p><p><b>CONCLUSION</b>No significant association between the HLA-DP and HLA-DQ loci and NPC in Han nationality in Hunan province was confirmed.</p>