Association of endothelial nitric oxide synthase gene rs7830 and rs3918188 polymorphisms with essential hypertension in Kazakh of Xinjiang region

AIM: To investigate the correlation between endothelial nitric oxide synthase (eNOS) rs7830 and rs3918188 locus polymorphisms and essential hypertension (EH) in the Kazakh of Xinjiang region. METHODS: Epidemiological case-control study was conducted. DNA was extracted by classic phenol-chloroform method, PCR amplification and purification. The rs7830 and rs3918188 of eNOS gene in 363 EH patients (EH group) and 370 normotensive controls (NT group) in the Kazakh of Xinjiang region were genotyped by the technique of SNaPshot single nucleotide polymorphism genotyping. The plasma levels of fasting blood glucose, uric acid, cholesterol and triglyceride were measured by biochemical methods. Determination of body mass index and waist-hip ratio was also conducted. RESULTS: Age (P<0.01), body mass index (P<0.01), triglyceride (P<0.01), low-density lipoprotein (P<0.05) and apolipoprotein A1/B (P<0.05) were the independent factors for EH in the Kazakh of Xinjiang region. No difference of eNOS gene rs7830 and rs3918188 loci in the genotype frequency and the allele frequency distribution between EH patients and normotensive controls in the Kazakh of Xinjiang region was observed (P>0.05). The frequency distribution of CA, CC, AC and AA haplotypes from eNOS gene rs7830 and rs3918188 loci between EH group and NT group also had no difference in the Kazakh of Xinjiang region (P>0.05). CONCLUSION: Age, body mass index and triglyceride are the independent risk factors, while low-density lipoprotein and apolipoprotein A1/B are the independent protective factors for EH in the Kazakh of Xinjiang region. The polymorphisms of eNOS gene rs3918188 and rs7830 loci are not related to EH in the Kazakh of Xinjiang region.     

Genetic variants of IL-33 are associated with clinical phenotypes of inflammatory bowel disease in Han population of southern China

AIM：To investigate whether the single nucleotide polymorphisms (SNPs) of interleukin-33 (IL-33) gene are associated with inflammatory bowel disease (IBD) in the Han population of southern China. METHODS：Eight tag-SNPs were selected from the IL-33 gene using the HapMap database. These tag-SNPs were genotyped in 250 Crohn disease (CD) patients, 115 ulcerative colitis (UC) cases and 622 healthy controls by MALDI-TOF MS assay. RESULTS：No difference of the distribution frequencies of genotypes and alleles between the cases and the controls was observed (P>0.05). Genotype-phenotype analysis suggested that several sites were associated with clinical phenotypes of CD.The T allele of SNP rs10118795 was a protective factor for extra-intestinal manifestation (EIM; P<0.05, OR=0.513, 95% CI： 0.281~0.938), while the CC genotype of SNP rs7025417 (P<0.05, OR=1.363, 95% CI： 1.006~1.846) was a risk factor for EIM. The C allele of rs10118795 decreased the risk for developing perianal lesions (P<0.05, OR=0.480, 95% CI： 0.232~0.994), while the CC genotype of rs10975519 was a risk factor for perianal lesions (P<0.05, OR=2.054, 95% CI： 1.053~4.009). The G allele of rs10975509 increased the risk of upper gastrointestinal CD (P<0.05, OR=3.570, 95% CI： 1.328～9.600), and the A allele of it increased the risk for developing ileocolonic CD (P<0.05, OR=0.613, 95% CI： 0.377~0.996). In the aspect of treatment, the genotypes of rs10118795, rs10975509 and rs7025417 were associated with mucosal healing after infliximab treatment for 30 weeks (P<0.05, P<0.01 and P<0.05). In the UC patients, no significant effect of the selected 8 tag-SNPs on the UC phenotypes was observed. CONCLUSION：Eight polymorphisms of IL-33 do not increase the risk of CD and UC in the Han population of southern China, but some of them have an effect on the clinical phenotypes of CD, and 3 SNPs may be potential markers for prediction of effectiveness of infliximab treatment.     

Genetic polymorphisms of RTN4 gene in Chinese Guangxi population

AIM: To investigate the distribution characteristics of rs2920891A/C and rs17046647A/G polymorphisms of RTN4 gene in Guangxi population, and to compare the differences among different populations. METHODS: The genotypes of RTN4 gene at rs2920891A/C and rs17046647A/G in 323 healthy persons of Guangxi were performed by the technique of SNaPshot and DNA sequencing. The results were compared with the alleles and genotypes of other populations (HapMap-CEU, HapMap-HCB, HapMap-JPT and HapMap-YRI in HapMap). RESULTS: In Guangxi population, 3 genotypes, AA, AC and CC, and 2 alleles, A and C, were found in rs2920891A/C. The allele frequencies between male and female showed significant differences (P<0.05). The genotype and allele frequencies compared with HapMap-JPT, HapMap-CEU and HapMap-YRI had differences with statistical significance (P<0.05). Three genotypes, AA, AG and GG, and 2 alleles, A and G, were found in rs17046647A/G. The genotype and allele frequencies between male and female showed no significant differences (P>0.05), but there were significant differences of the genotype and allele frequencies as compared with HapMap-JPT, HapMap-CEU and HapMap-YRI (P<0.01).CONCLUSION: The rs2920891A/C and rs17046647A/G polymorphisms of RTN4 gene in Chinese Guangxi population are different from those in other races.     

Genetic polymorphism of caspase-7 isoform β in patients with rheumatoid arthritis

AIM: To investigate the association between the rs2227309 polymorphism of cysteinyl aspartate-specific protease-7 (caspase-7) isoform β and the genetic susceptibility in rheumatoid arthritis (RA) patients in Taizhou of China. METHODS: Genotyping of rs2227309 of caspase-7 isoform β gene was performed in 204 RA patients and 203 matched healthy controls using TaqMan single nucleotide polymorphism (SNP) genotyping assays. RESULTS: The genotype frequencies of GG, AG and AA of caspase-7 polymorphism in the RA patients were 33.3%, 53.4% and 13.2%, respectively, and 33.0%, 44.3% and 22.7% in the healthy individuals,respectively. There was a significant difference in caspase-7 genotype frequencies between the RA patients and healthy controls (P<0.05). The frequency of GG+AG genotype in RA patients was higher than that in healthy controls with significant difference (P<0.05, OR=1.921, 95%CI: 1.140~3.236). The frequencies of the G allele were 60.0% and 55.2% in the RA patients and the healthy individuals,respectively. No significant difference was observed in allele frequency between the RA patients and healthy controls (P>0.05, OR=1.221, 95%CI: 0.924~1.613). CONCLUSION: The rs2227309 polymorphism of caspase-7 isoform β gene is associated with the susceptibility to rheumatoid arthritis. The high production of the non-functional variant of caspase-7 may reduce the apoptosis of rheumatoid synovial cells, indicating the mechanism of this association.     

Association of OPG gene single nucleotide polymorphisms with susceptibility to rheumatoid arthritis in Chinese Han population

AIM：To investigate the association of osteoprotegerin (OPG) gene single nucleotide polymorphisms (SNPs), 163A/G (rs3102735) and 245T/G (rs3134069), with susceptibility to rheumatoid arthritis (RA) in Chinese Han population. METHODS：A total of 205 patients with RA and 171 healthy control subjects were enrolled into this study. Genotyping was performed by polymerase chain reaction-based restriction fragment length polymorphism and subsequently confirmed by DNA sequencing. Odds ratio (OR) and 95% confidence intervals (CI) were calculated for the risk genotypes and alleles. RESULTS：OPG gene polymorphisms 163A/G and 245T/G were conformed to the Hardy-Weinberg equilibrium. The statistical differences in the genotypes of AA, AG and GG at 163A/G locus were found in RA and controls. The G allele was associated with an increased risk of RA, with OR of 1.219 (95％ CI: 1.066~2.339). No significant difference was observed between RA group and control group with respect to genotypic and allelic frequencies of OPG gene 245T/G (P>0.05）. CONCLUSION：The OPG gene 163A/G SNP may be associated with RA susceptibility, and G allele may be the risk factor for developing RA.     

Distribution characteristics of polymorphisms of interleukin-22 gene in Guangxi population and their association with serum lipid levels

AIM: To investigate the distribution characteristics of interleukin-22 (IL-22) gene rs2227485C/T and rs2227491A/G polymorphisms in Guangxi people and the distribution differences with other ethnic groups, and to explore the difference levels of common lipid indexes in different genotypes. METHODS: SNaPshot technique and DNA sequencing were used in 280 Guangxi persons to examine IL-22 genotypes and to analyzed the distribution frequencies of allele and genotype in these sites. The distribution frequencies in different sexes, and the differences between groups and diffe-rence levels of common lipid indexes in different genotypes were analyzed statistically. RESULTS: Three genotypes of CC, CT and TT were found in rs2227485C/T with the frequency distribution of 17.1%, 49.3% and 33.6%, respectively. No significant difference between different sexes of each genotype and allele frequency in the Guangxi population was observed (P>0.05). Compared with the distribution frequencies of genotype and allele in HapMap-TSI, HapMap-HCB, HapMap-JPT and HapMap-MEX, those in Guangxi population showed statistically significant differences (P<0.05). Three genotypes of AA, AG and GG were found in rs2227491A/G with the frequency distribution of 16.1%, 52.8% and 31.1%, respectively. There was no significant difference between different sexes of each genotype and allele frequency in the Guangxi population (P>0.05). The significant differences of genotype frequencies among Guangxi population, HapMap-TSI, HapMap-JPT and HapMap-MEX were detected (P<0.05). Compared with the other 4 populations, allele frequencies in Guangxi population had significant difference (P <0.05). There were significant differences in the levels of HDL-C and LDL-C among the 3 genotypes of rs2227491A/G. The level of HDL-C had difference between AG/AA genotype and GG genotype. In addition, the level of LDL-C had difference between AG/GG genotype and AA genotype (P<0.05). CONCLUSION: rs2227485C/T and rs2227491A/G polymorphisms of IL-22 gene have differences in different populations. The rs2227491A/G polymorphism may be associated with serum lipid levels.     

Association between IL-6-572C/G as well as IFNAR1-168G/C and hepatitis B virus infection in populations of Dai and Han ethnicities in Yunnan Province

ATM: To explore the association between IL-6-572C/G (rs1800796) as well as interferon alpha receptor 1 (IFNAR1)-168G/C (rs2257167) and prognosis after hepatitis B virus (HBV) infection in populations of Dai and Han ethnicities in Yunnan Province. METHODS: The blood samples were collected from Dai people and Han people, each nation including 100 healthy controls and 200 infected individuals (100 spontaneous recovery individuals and 100 chronic patients). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing were used to identify the gene type. RESULTS: In Dai people, no significant difference was found between genetic polymorphism of -572C/G and prognosis after HBV infection. The differences of C and G alleles between spontaneous recovery group and chronic hepatitis B group, and healthy controls and HBV infection group were not statistically significant. Meanwhile, GG and CG genotypes were a vital protective factor for the person who developed into a chronic heptatitis B patient under the G allele dominance mode (GG+CG/CC) (P<0.05). In Han people, no statistically significance for IL-6-572C/G genotype and allele distribution in each group comparisons had been found, as well as the C allele recessive mode and C allele dominance mode. For the above 4 indicators, no statistically significant difference of IFNAR1-168C/G in Dai and Han people had been found.CONCLUSION: The GG+CG genotype of IL-6-572C/G may be a protective factor for the HBV-infected Dai people to develop into chronic hepatitis B patients. However, there is no significant association between the IFNAR1-168G/C polymorphism and prognosis after HBV infection in the 2 ethnicities.     

Association analysis between two SNPs in SNCA and PARK16 genes and Parkinson disease in a Han Chinese population in Liaoning area

AIM: To investigate the genotypic frequency of rs3857059 in SNCA gene and rs16856139 in PARK16 gene for determining the potential genetic risk factors of Parkinson disease (PD) in a Han Chinese population in Liaoning area of China. METHODS: The genomic DNA from 213 PD patients and 214 matched controls was amplified in the multiplex PCR system and subsequently genotyped by digestion with endonuclease Pvu II. Genetic parameter and association studies were carried out with SPSS 13.0 and PLINK 1.07 software. RESULTS: We accurately detected all genotypes in the 2 loci with PCR-restriction fragment length polymorphism (RFLP) techniques. The gene frequency of G allele in the rs3857059 locus was higher in PD group than that in control group with statistical significance (χ²= 7.592,P<0.01, OR=0.677, 95% CI=0.517~0.888). The T allele frequency in the rs16856139 locus was lower in PD group than that in control group and statistical result revealed a significant difference (χ²=11.511, P<0.01, OR=0.390, 95% CI=0.227~0.669). CONCLUSION: The 2 SNPs investigated in SNCA and PARK16 genes are likely to play roles as common risk factors for PD disease in the Han Chinese population.     

Association of SOX5 polymorphisms in chronic obstructive pulmonary disease-related pulmonary hypertension

SOX5) gene single nucleotide polymorphisms (SNPs) among stable chronic obstructive pulmonary disease (COPD) patients,COPD with pulmonary hypertension (PH) patients and healthy controls,and to explore the association of the SOX5 SNPs in COPD-related PH.METHODS: From April 2013 to April 2015,250 patients with stable COPD were enrolled continuously in Ningxia People's Hospital according to COPD treatment guidelines (2013 edition).All the patients received echocardiography,and were divided into COPD with PH group[pulmonary artery systolic pressure (PASP)≥50 mmHg,n=103] and COPD without PH group (PASP<50 mmHg,n=147).The healthy persons (matched for age,sex,race and smoking index,n=127) were selected as control group at the same period.Genotyping of SOX5 gene rs10842262 and rs11046966 loci was performed using MassARRAY genotyping system (Sequenom).Genotype frequencies were calculated.RESULTS: Age,sex and smoking index showed no significantly difference between control group and COPD group,neither between COPD with PH group and COPD without PH group.Genotype frequencies of SOX5 gene rs10842262 and rs11046966 loci between control group and COPD group was of significant difference (P<0.05).Genotype frequencies of SOX5 gene rs10842262 and rs11046966 loci showed no significant difference between COPD with PH group and COPD without PH group.CONCLUSION: SOX5 gene rs10842262 and rs11046966 loci may play an important role in COPD,but not in COPD-related PH.     

Association of polymorphism of Fc receptor γ chain gene at position-29 in promoter with the susceptibility to systemic lupus erythematosus in southern Chinese

AIM:To detect the association between the polymorphism of Fc receptor γ chain gene at position-29 in promoter and systemic lupus erythematosus(SLE).METHODS:The genotypes at position -29 in promoter of Fc receptor γ chain gene were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 180 patients with SLE and 140 ethnically matched controls in southern China.RESULTS:The frequencies of TT genotype(33.3%) and T allele (54.4%) at position -29 in patients with SLE were significantly higher than those in controls (17.2% and 42.9%, respectively), whereas, the frequencies of GG genotype (24.4%) and G allele (45.6%) in patients with SLE were remarkably lower than those in controls (31.4% and 57.1%, respectively) (P＜0.05). The TT genotype and T allele at position -29 were not associated with lupus nephritis in SLE patients (P＞0.05).CONCLUSION:Our results indicate that the T allele at position -29 in promoter of Fc receptor gene probably contributes to the susceptibility to SLE, but does not play a role in the occurrence of lupus nephritis.     

Association of Fas promoter-670 polymorphism with systemic lupus erythematosus in southern Chinese

AIM: To investigate whether Fas promoter-670 polymorphism is associated with systemic lupus erythematosus(SLE) in Southern Chinese. METHODS: 103 SLE patients and 110 controls were studied. Fas promoter -670 polymorphism was typed by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). RESULTS: No statistically significant differences were found when Fas promoter -670 genotype and allele frequencies were compared between the SLE and the controls. Similarly, no significant differences were seen between the male and female SLE and the controls, the SLE with lupus nephritis (LN) and the controls, the SLE with LN and the SLE without LN. CONCLUSION: Fas promoter -670 polymorphism does not appear to be associated with susceptibility to SLE in Southern Chinese.     

HLA-DRB1 genotyping and its relation with chronic HBV infection in patients

AIM: To study the HLA-DRB1 genotype and their relation with HBV infection in Shaanxi Han patients. METHODS: HLA-DRB1 genotyping was conducted in 108 case of chronic HBV infection and 108 health controls as well as 32 asymtomatic HBsAg carriers by using polymerase chain reaction-sequence specific primer method. All the patients, asymtomatic HBsAg carriers and health subjects were residents of Shaanxi district and belonged to Han nationality. The association between HLA-DRB1 genotype and different replication of HBV was also studied. RESULTS: DRB1*04, DRB1*09, DRB1*12 and DRB1*15 were the most common genotypes in Shaanxi Han residents with the frequency of 16.2%, 12.5%, 11.6% and 13.4%, respectively. Compared to 108 health controls, the allele frequency of HLA-DRB1*03 (10.6% of HBV patients versus 3.7% of health controls, odds ratio=3.10; P<0.05) and HLA-DRB1*07 (17.6% of HBV patients versus 9.3% of health controls, odd ratio=2.09; P<0.05) were markedly higher. The allele frequency of HLA-DRB1*15 (13.4% of HBV patients versus 6.9% of health controls, odds ratio=0.48; P<0.05) was obviously lower than than in HBV patients. CONCLUSION: HLA-DRB1*03 and HLA-DRB1*07 are closely related with susceptibility to chronic hepatitis B infection, and DRB1*15 is closely related with resistance to chronic hepatitis B infection. These finding suggest that host HLA class II gene is an important factor determining the outcome of HBV infection.     

Association of single nucleotide polymorphisms of IL-1, IL-10 and TNF-β with rheumatoid arthritis in Chinese Han population from Quanzhou

AIM: To explore the genetic characteristics of enrolled rheumatoid arthritis and genetic mechanisms of rheumatoid arthritis (RA) by studying the associations of single nucleotide polymorphisms (SNPs) with rheumatoid arthritis in Chinese Han population from a very high prevalence area of rheumatoid arthritis, Quanzhou. METHODS: A case-control study of 155 rheumatoid arthritis patients (RA group) and 170 normal controls (control group) from Quanzhou were enrolled. All of 5 SNPs were genotyped by allele-specific polymerase chain reaction (PCR) and analyzed by SPSS 19.0. χ²-test was applied to predict Hardy-Weinberg equilibrium, and allele and genotype frequencies between RA group and control group were compared. Logistic regression models were used to analyze SNPs. Link disequilibrium analysis and haplotype analysis were performed with SHEsis software. RESULTS: Total of 1 SNP in control group was confirmed by Hardy-Weinberg equilibrium test (P>0.05), and 1 SNP in RA group was confirmed by Hardy-Weinberg equilibrium test (P>0.05). Allele frequencies of 4 SNPs were significantly different between control group and RA group (P <0.05). CONCLUSION: The SNPs of IL-10 rs1800893, IL-1β rs16944, TNF-β rs2009658 and TNF-β rs1041981 were associated with the incidence of rheumatoid arthritis in Chinese Han population of Quanzhou. Allele G of IL-10 rs1800893, allele G of IL-1β rs16944, allele C of TNF-β rs2009658 and allele C of TNF-β rs1041981 can be used as potential genetic markers for the diagnosis of RA in Quanzhou, Fujian.     

B allele in Iα1 hs1,2 VNTR region is associated with IgA nephropathy

AIM: To investigate the relationships between Iα1 hs1,2 VNTR polymorphism and IgA nephropathy. METHODS: Four hundred and ninteen patients with IgA nephropathy and their first-degree relatives were recruited. Two hundred and one sex and age-matched normal Chinese Han volunteers were also recruited as controls. After extracting genomic DNA, the VNTR genotypes of Iα1 hs1,2 region were determined by PCR and electrophoresis, and the results were analyzed by transmission disequilibrium test (TDT) and haplotype relative risk (HRR) in the families, and Chi-Square test in the case-control analysis. RESULTS: ① TDT analyses showed that B allele of the Iα1 hs1,2 VNTR region was significantly more transmitted from heterozygous parents to patients than expected (101 Trios, χ2=6.818, P＜0.01), extended TDT produced the same results (164 families, χ2=7.583, P＜0.01). ② Consistent with the TDT results, HRR also showed that B allele was over-transmitted to patients (P＜0.05, χ2=4.122, HRR=1.180), and the BB genotype conferred a higher risk of developing the disease (P＜0.05, χ2=4.411, OR=1.538). ③ The case-control study indicated that the B allele had a higher frequency in the IgA nephropathy group (χ2=6.968, P＜0.05). CONCLUSION: B allele in Iα1 hs1,2 VNTR region is associated with susceptibility to IgA nephropathy.     

Relationship between IL-1 gene polymorphism and severity of rheumatoid arthritis and secretion of IL-1

AIM: To determine the influence of interleukin-1α(IL-1α) and β(IL-1β) gene polymorphisms on rheumatoid arthritis(RA) disease severity and secretion of IL-1β. METHODS: The study included 136 RA patients and 102 healthy controls. PCR-RFLP was used to detect site mutation at IL-1 gene. Meanwhile the IL-1β was also measured in the supernatant of the cultured and stimulated peripheral blood mononuclear cells(PBMC). RESULTS: No difference in the allele frequencies or genotypes of the IL-1α gene polymorphisms was found between the controls and RA patients.IL-1β allele 2 was overrepresented in patients with erosive RA but not in nonerosive patients. The patients with IL-1β allele 2 had a higher swollen joint index, higher tender joint index and erythrocyte sedimentation rate than those without IL-1β allele 2.The IL-1β in supernatant of stimulated PBMC from patients with IL-1β allele 2 had a higher level than that from those without allele 2. CONCLUSION: IL-1 gene polymorphisms may influence the occurrence of RA. Detection of IL-1β allele 2 have a potential prognostic value in RA.     

Association of IFN-γ and IL-4 gene polymorphisms with childhood bronchial asthmatic susceptibility and the levels of plasma IFN-γ,IL-4 and IgE

AIM: To investigate the gene polymorphisms of interferon-γ(IFN-γ) and interleukin-4(IL-4) and the association with asthmatic susceptibility and the levels of plasma IFN-γ, IL-4 and IgE of asthmatic children. METHODS: 100 asthmatic children and 122 control children were enrolled the study. The genotypes of IFN-γ gene-179G/T polymorphism, IL-4 gene-33C/T and-589C/T polymorphisms were tested by PCR-RFLP.The genotype of IFN-γ gene +874A/T polymorphism was tested by AS-PCR.The CA repeat polymorphism of IFN-γ gene was detected by capillary electrophoresis technique.The levels of serum IFN-γ, IL-4 and IgE were measured by ELISA. RESULTS: 100 asthmatic children and 122 control children were all GG homozygotes at -179 locus of IFN-γ gene.-179 locus of IFN-γ gene has no mutation. The genotypes and allele frequency of IFN-γ gene +874A/T and CA repeat polymorphisms showed no significant difference between asthmatic children and the control(P>0.05). An association was revealed between IFN-γ gene +874A/T polymorphism and the level of plasma IFN-γ.The level of IFN-γ was lower in AA genotype than in AT genotype(P<0.05). The genotypes and allele frequency of IL-4 gene -33C/T and -589C/T polymorphisms showed significant difference between asthmatic children and the control(P<0.05).The levels of plasma IL-4 and IgE were higher in TT genotype at -33 locus and -589 locus than those in CT genotype, but only -33C/T polymorphism was associated with the level of plasma IL-4(P<0.05). CONCLUSION: The IFN-γ gene +874A/T and CA repeat polymorphisms were not correlated with asthmatic susceptibility, but there is significant correlation between the level of IFN-γ and +874A/T polymorphism. TT genotype of IL-4 gene -33 locus and -589 locus maybe the susceptible genotype of asthma in children, and the -33 locus polymorphism is associated with the level of IL-4.     

Relationship between RUNX3 gene 364 locus C→T mutation and gastric cancer in Chinese

AIM: To study the frequency difference of RUNX3 gene 364 locus C→T mutation between normal people(controls) and gastric cancer (GC) patients, and mutation in gastric mucosa of subjects with H.pylori infection. METHODS: Genomic DNA was extracted from peripheral blood and gastric mucosal biopsy specimens of normal people and GC patients in lower or higher prevalence region. Gene mutation was analyzed by PCR-RFLP. RESULTS: The frequency of RUNX3 T/T genotype was no significant difference between controls and GC in lower (χ2=0.57, P>0.05) or higher prevalence region (χ2=0.16, P>0.05). A higher mutation rate in mucosal tissue infected with H.pylori was not discovered. CONCLUSION: RUNX3 gene C364T mutation may be not a genetic susceptibility to GC in Chinese. The mutation is impossibly involved in the pathway of H.pylori infection resulting in gastric carcinoma.     

Genetic polymorphisms of TLR2 locus in Chinese Cantonese population

AIM: Toll-like receptor 2 ( TLR2 ) was a significant pathogen recognition receptor in innate immune system. The aim of this study was to investigate the distribution of TLR2 polymorphisms in the general population of Chinese Cantonese. METHODS: Peripheral blood samples were collected from 200 unrelated healthy Chinese Cantonese individuals. The functional regions of TLR2 locus, including promoter region and all three exons with their surrounding intronic regions were amplified using PCR and sequenced in a random sample of 24 subjects. TLR2 genotyping in other 176 subjects was performed using PCR-sequence specific primer and PCR. RESULTS: A total of 5 single nucleotides polymorphisms (SNPs) were detected, the two of which were novel. SNPs located in the coding region were all synonymous substitutions. The most common SNP was rs3804099 with the minor allele frequency of 26.3%. One 22 bp insertion/deletion (INDEL) polymorphism was found in exon 1 with the deletion allele frequency of 31.8%. All polymorphic sites were consistent with Hardy-Weinberg equilibrium. Neutrality test suggested that TLR2 in Chinese Cantonese did not significantly deviate from the neutral model. Linkage disequilibrium (LD) analysis showed complete LD between SNP-18945 C/T and SNP-18 883 C/G, and strong LD between SNP rs3804099 and SNP rs3804100. CONCLUSION: This is the first report on the distribution of TLR2 polymorphisms in the general population of China. It provided some ethnic specific polymorphisms, which might help in the further studies of disease association in Chinese.