广东汉族人群TLR2基因的多态性研究

目的:人类Toll样受体2(TLR2)是先天免疫系统中一个重要的病原微生物识别受体。本研究将建立广东汉族人群TLR2基因座位的功能性多态性图谱,为下一步疾病相关性研究打下基础。方法:收集200例健康、无亲缘关系的中国广东汉族人外周血液,随机抽取其中24例样品,对TLR2基因的启动子区、3个外显子以及它们周围的部分内含子序列进行聚合酶链式反应(PCR)扩增和直接测序,找出多态性位点,对剩余176例样品分别用序列特异性引物聚合酶链反应(PCR-SSP)及PCR技术对发现的单核苷酸多态性(SNPs)和插入/缺失(INDEL)多态性位点进行基因分型,分型结果进行Hardy-W e inberg平衡分析、中性进化分析以及连锁不平衡分析。结果:发现5个SNPs位点,其中2个位于启动子区的SNPs是首次发现,位于编码区的3个SNPs位点均为同义突变,频率最高的SNP是rs3804099,其次要等位基因频率为26.3%;在第1外显子区发现1个长度为22bp的INDEL多态位点(-196到-174),其缺失等位基因所占的频率为31.8%。所有多态性位点均符合Hardy-W e inberg平衡。中性检验显示广东汉族人群TLR2基因符合中性进化假说。连锁不平衡分析显示位于调控区的-18945 C/T和-18883 C/G 2位点之间完全连锁,而位于编码区的rs3804099和rs3804100两位点之间紧密连锁。结论:本研究首次建立了汉族正常人群TLR2基因座位的功能性多态性图谱,并研究了其分布频率,发现了一些种族特异性的多态性位点,为今后开展汉族人基因多态性与疾病相关性研究以及人群进化研究提供了重要资料。     

广东汉族正常人群TLR4基因单核苷酸多态性研究(英)

目的：人类Toll样受体4（TLR4）是先天免疫系统中一个重要的病原微生物识别受体。本研究将建立中国汉族正常人群TLR4基因座位的单核苷酸多态性图谱。方法：收集191例健康、无亲缘关系的中国广东汉族人外周血液,通过对TLR4基因的启动子区、3个外显子区以及它们周围的内含子区进行PCR扩增和测序,得到汉族正常人群TLR4基因座位单核苷酸多态性图谱及其频率分布特点。结果：共发现8个单核苷酸多态性位点,其中5个是首次发现的新位点。分布频率最高（0.283）的单核苷酸多态性位点是-1607 C/T。常见于高加索人中的2个非同义突变Asp299Gly和Thr399Ile在汉族人中没有被发现。中性检验显示汉族人群TLR4基因符合中性进化模型。结论：本研究建立了汉族正常人群TLR4基因座位的单核苷酸多态性图谱,发现了一些种族特异性的单核苷酸多态性位点,这些工作将为今后开展汉族人基因多态性与疾病相关性研究以及人群进化研究提供一定的帮助。     

利用生物信息学技术挑选TLR2基因标签单核苷酸多态性位点

目的利用生物信息学技术挑选中国人群中的TLR2基因标签单核苷酸多态性(SNP)位点。方法利用NCBI数据库,确定TLR2基因研究范围,并利用Hapmap数据库下载中国人群的TLR2基因的SNPs数据;使用Haploview4.0软件对TLR2基因进行了连锁不平衡分析;通过对D值95%可信区间上下限的分析,在整个TLR2基因范围内构建单倍域(haplotype block);然后根据单倍域内SNPs之间的r2值和LOD值,挑选标签SNP;最后根据单倍域内的单倍型所占比例,挑选出标签SNP代表的单倍型。结果在中国人群中,TLR2全基因范围内共构建2个单倍域,挑选出3个标签SNPs(3013A/G、19216T/C、22215G/T)。同时,确定了单倍域内的标签SNPs分别代表的单倍型。结论中国人群的TLR2基因的3个SNPs位点(3013A/G、19216T/C、22215G/T)是最有代表性的标志性位点,可被选为标签SNPs,并指导中国人群TLR2基因与脓毒症关联研究。     

浙江地区汉族人群caspase-3基因三个位点的单倍型研究

目的分析汉族人群caspase-3基因的单核苷酸多态性(singlenucleotidepolymorphisms,SNPs)位点及其构成的单倍型,为研究caspase-3基因对凋亡调节机制的个体差异提供线索。方法用变性高效液相色谱技术和DNA测序技术检测caspase-3基因的调控区、第2～7外显子及部分侧翼序列的多态性位点;分析位点间的连锁不平衡关系,估算它们构成的单倍型。结果共检出3个SNP位点(C829A、A17532C、C20541T),分别位于caspase-3基因的5′端调控区、第4内含子和3′调控区;3个位点间存在强连锁不平衡,其中位点A17532C与C20541T呈完全连锁不平衡;54.3%的C-829/A-17532/C-20541是汉族人群的主要单倍型。结论浙江地区汉族人群caspase-3基因上的3个SNP位点间存在强连锁不平衡,它们构成的主要单倍型不同于北美人群。     

骨保护素基因单核苷酸多态性与类风湿关节炎发病的相关性研究

 目的：探讨骨保护素（OPG）基因163A/G及245T/G单核苷酸多态性（SNPs）与我国汉族人群类风湿关节炎（RA）发病的相关性。方法：采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）技术检测我国南方汉族正常人群及RA患者的OPG 163A/G 和245T/G 2个SNP位点;进行Hardy-Weinberg平衡检验;计算基因型和等位基因频率,及这2个位点的连锁关系,并分析这2个SNP位点与RA的关系。结果：所研究基因分布符合Hardy-Weinberg平衡,163A/G 位点基因型AA、AG、GG分布频率在2组比较有显著差异（P<0.05）;等位基因A、G分布比较在2组有显著差异（P<0.05）,携带163GG基因型者发生RA的危险性是非携带者的1.219倍（OR=1219, 95％CI：1066~2.339, P<0.05)。但245T/G位点各基因型及等位基因频率在2组中均未见差异（P>005）。结论：OPG 基因 163A/G SNP可能与我国汉族人群RA发病相关,携带G等位基因可能是发病的危险因素。     

TIM-3基因-1516、-574、4259单核苷酸多态性及连锁不平衡分析

目的 调查T细胞免疫球蛋白粘蛋白.3基因(T cells immunoglobulin mucin-3 gene,TIM-3)-1516、-574、4259单核苷酸多态性(single nucleotide polymorphisms,SNP)的发生频率及是否存在连锁不平衡(linkage disequilibrium, LD)关系.方法 采用等位基因特异性聚合酶链反应(allele-specific polymerase chain reaction, AS-PCR)方法对湖北地区147名健康个体TIM-3基因-1516G/T、-574T/G、4259G/T 3个SNP位点进行基因分型,应用软件Arlequin V3.1对3个SNP位点进行LD及Hardy-Weinberg平衡分析,并计算单倍型频率及单倍型组成.结果 3个TIM-3基因SNP位点等位基因频率分布符合Hardy-Weinberg平衡.湖北地区147名正常个体T/M-3基因-1516G/T、-574T/G、4259G/T 3个SNPs的次要等位基因发生频率分别是8.5%、1.0%、2.0%.TLM-3基因3个SNP主要组成4种单倍型:G-G-G、G-G-T、T-G-T、G-T-T;其频率分别为2.0%、88.4%、8.5%、1.0%.通过对这3个SNP位点两两间进行LD分析,发现所有的连锁不平衡系数D'(coefficient of linkage disequilibrium, D')值都为1.结论 湖北地区人群T/M-3基因-1516G/T、-574T/G、259G/T 3个SNP位点呈完全连锁不平衡.本研究结果提供了中国湖北地区汉族人群TIM-3基因这3个SNP的群体遗传学资料,并且为寻找与免疫介导性疾病相关单倍型奠定了基础.     

江苏汉族人群XRCC1基因的遗传多态性研究

目的探讨江苏省汉族正常人群中X线修复交叉互补基因1（XRCC1）常见的两个单核苷酸多态（SNPs）C26304T和G27466A的遗传分布特点。方法采用聚合酶链反应（PCR）及限制性片段长度多态（RFLP）方法分析江苏省扬中地区511名健康汉族人的XRCC1基因C26304T和G27466A的基因多态性。结果511名江苏汉族人的XRCC1 C26304T基因型CC、CT、TT的频率分别为45．8％、42．7％和11．5％,等位基因C、T的频率分别为67．1％和32．9％。G27466A基因型GG、GA、AA的频率分别为68．9％、29．0％和2．1％,等位基因G、A的频率分别为83．4％和16．6％。江苏人群的C26304T基因型频率和等位基因频率分布与浙江、台湾人群均无明显差异（P〉0．05）,但与意大利人、美国白人、美国黑人的差异具有显著性（P〈0．05）。江苏人群的G27466A基因型频率和等位基因频率分布与浙江人、台湾人、意大利人、美国白人、美国黑人的差异均具有显著性（P〈0．05）。结论本研究揭示了江苏汉族人群XRCC1基因C26304T和G27466A的等位基因频率和基因型频率分布特点;证实了C26304T和G27466A位点的等位基因和基因型频率存在种族、地区差异。     

纤维蛋白原Bβ基因启动区单核苷酸多态性及连锁不平衡分析

目的　探讨纤维蛋白原 B(fibrinogen,FGB)基因启动区 - 14 8C/ T、- 4 5 5 G/ A、- 85 4 G/ A3个位点单核苷酸多态性 (single nucleotide polymorphism,SNP)在中国南方汉族人群的分布特征及连锁不平衡关系。方法　应用聚合酶链反应 -限制性片段长度多态性技术结合 DNA测序分析检测 377名中国南方汉族人 FGBβ基因型和等位基因的分布频率 ,群体数理遗传学方法分析 FGBβ 3个基因位点 SNP的遗传平衡吻合度和相互间连锁不平衡关系。结果　 3个 FGBβ SNP位点等位基因频率分布符合 Hardy-Weinberg平衡。检出了 FGBβ3个位点 SNP的共 9种基因型 ,- 14 8CC、CT、TT基因型频率分别为0 .5 97、0 .35 8和 0 .0 4 5 ;- 4 5 5 G/ A SNP各基因型频率与 - 14 8C/ T SNP相同 ;- 85 4 GG、GA、AA基因型频率分别为 0 .82 0、0 .178和 0 .0 0 2。各 SNP位点的少见型等位基因频率分别是 0 .2 2 4 (- 14 8T)、0 .2 2 4 (-4 5 5 A)、0 .0 92 (- 85 4 A) ;常见型等位基因频率分别为 0 .776 (- 14 8C)、0 .776 (- 4 5 5 G)、0 .90 8(- 85 4 G)。男女性别间各基因型和等位基因分布频率差异无显著性 (P>0 .0 5 )。经连锁不平衡检验 ,- 14 8C与 - 4 5 5 GSNP为完全一致型 ,- 85 4 G/ A与 - 14 8C/ T、- 4 5 5 G/ A为随机分布。结     

β2—肾上腺素能受体基因单核苷酸多态性及在汉族人群中的分布

目的 研究中国人β2－肾上腺素能受体（beta2-adrenoceptor,β2－AR）基因单核苷酸多态性（single nucleotide Polymorphism.SNP),并观察这些SNPs在汉族人群中的多态性分布。方法 应用荧光标记自动测序法测定来自安徽大别山地区80名非亲缘关系人群β2－AR基因序列,确定单核酸多态位点及基因型。结果 在3．8kb长度范围内共发现8个SNPs,其中5个位于编码区,平均274bp出现一个SNP,3个位于调控区,平均721bp出现一个SNP,与国外报告相比－468－G,－367T－C,4．－47C－T,－20T－C,＋79C→G,＋100G→A, 491C→T, 1098T→C未在研究人群中检测到,各SNPs等位基因频率在人群中的分布符合Hardy-Weinberg平衡,结论 β2－AR基因SNPs呈不均匀分布,且具有很大的种族差异,其等位基因频率在人群中分布符合Hardy=-Weinberg 平衡。     

唐山地区汉族人群脑梗死患者IL-6基因-572C/G多态性研究

目的:探讨唐山地区汉族人群脑梗死患者IL-6基因-572C/G多态性及其分布特点。方法:应用聚合酶链反应(PCR)和限制性片段长度多态性(RFLP)方法测定唐山地区汉族人群中157例脑梗死患者的IL-6基因-572C/G的基因多态性。结果:脑梗死患者和健康人群的C等位基因频率均明显高于G等位基因频率(P0.05)。经Hardy-Weinberg吻合度检验,脑梗死人群和健康人群的-572C/G位点基因型个体数的观察值和期望值差异均无显著性(P0.05)。本组脑梗死患者人群和健康人群中不同性别之间IL-6-572C/G的基因型及等位基因频率分布的差异均无统计学意义(P0.05)。结论:唐山地区汉族人群脑梗死患者中可能存在IL-6基因-572C/G多态性,C等位基因可能为常见基因,G等位基因可能为少见基因。     

TLR4基因多态性在中国人群中的初步研究

目的检测中国人Toll样受体4(Toll—like receptor 4．TLR4)基因调控区和编码区的单核苷酸多态性(single nucleotide polymorphisms，SNPs)．寻找TLR4基因的遗传标记。方法采用直接测序的方法检测基因的5′区、编码区、部分内含子区和3′区，以确定中国人群中TLR4基因SNP的位置和类型，并用聚合酶链反应-限制性片段长度多态性对重庆汉族样本进行了抽样调查。结果在4．98kb的测序范围内，发现5个新的SNP，3个位于5′区．2个位于3′非翻译区。在重庆地区汉族样本中．两个高频分布SNP的等位基因频率分别是0．266和0．404。结论在TLR4基因新发现的两个高频多态性位点在我国人群中比较常见，可以作为关联分析的遗传标记。     

Single nucleotide polymorphisms and haplotypes of TLR6 gene in Chinese Cantonese population

Sequence polymorphisms in the coding region of Toll-like receptor 6 gene were investigated in Chinese Cantonese population. By amplifying and sequencing a 2787 bp segment containing the entire coding region of TLR6 gene of 191 individuals in Chinese Cantonese population, a total of seven single nucleotide polymorphisms (SNP) along with their frequencies were detected. Comparing these data with SNP published in dbSNP database of National Center for Biotechnology Information (NCBI), two SNP (+176T/C and +1408G/T) were firstly reported, and five SNP caused amino-acid substitution. Sixteen haplotypes and their distributions were reconstructed. Linkage disequilibrium analysis and neutrality test were also performed. Comparing with other ethnic populations, Chinese Cantonese displayed obvious differences in TLR6 polymorphism. It may in part reflect the ethnic diversity of pathogen susceptibility and facilitate to develop the disease-association studies as well as population genetics and evolutionary research.     

Rarity of TLR4 Asp299Gly and Thr399Ile polymorphisms in the Korean population

PURPOSE: Activation of the innate immune system and chronic low-grade inflammation are thought to be involved in the pathogenesis of atherosclerosis and also thought to be associated with type 2 diabetes and its complications. As a receptor for bacterial lipopolysaccharide and heat-shock proteins, Toll-like receptor 4 (TLR4) is one of the central regulators of the immune response. Recent studies have reported an association between TLR4 polymorphisms and diabetes and its complications in Caucasian populations. MATERIALS AND METHODS: In this study, we analyzed the association between TLR4 gene polymorphisms in patients with features of type 2 diabetes and healthy controls in Korea. Two polymorphisms of the TLR4 gene (Asp299Gly and Thr399Ile) were examined in 225 diabetic patients and 153 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and single-strand conformation polymorphism (SSCP). RESULTS: No Asp299Gly or Thr399Ile mutations were detected in any of the 378 subjects. Seven subjects from each group who had slightly different SSCP patterns were selected for sequencing, but we found no TLR4 polymorphisms on Exon3. The Asp299Gly and Thr399Ile TLR4 gene polymorphisms were absent in both groups, which was similar to the results for Japanese and Chinese Han subjects. CONCLUSION: Our data and other Asian data suggest that a racial difference can be found in the frequency of the TLR4 polymorphism.     

Novel and previously reported single-nucleotide polymorphisms in the human 5-HT(1B) receptor gene: no association with cocaine or alcohol abuse or dependence

Evidence from animal self-administration and human genetics studies suggests that the serotonin(1B) (5-HT(1B)) receptor may be involved in modulating responses to cocaine or alcohol. We hypothesize that polymorphisms, including single-nucleotide polymorphisms (SNPs), in the human 5-HT(1B) receptor gene, may be associated with individual differences in vulnerability to cocaine or alcohol abuse or dependence. A total of 210 subjects were studied, including individuals with a primary diagnosis (DSM-IV criteria) of cocaine abuse or dependence, alcohol abuse or dependence, and controls with no history of previous or current illicit drug or alcohol abuse or dependence. Genomic DNA samples were isolated from each individual. For 157 of the subjects, polymerase chain reaction (PCR) was used to amplify the entire coding region of the 5-HT(1B) receptor gene as well as parts of the 5' and 3' untranslated regions. PCR products were sequenced in forward and reverse directions on an automated sequencer. Amplified DNA from an additional 53 subjects was sequenced in the 5' untranslated region to gain additional data on the frequency of one identified SNP. Seven polymorphisms were identified: one novel SNP in the 5' untranslated region (UTR) of the gene (A-161T); one SNP not reported in any published scientific communication (but found to be recorded in GenBank) in the 3' UTR (A1180G); two novel dinucleotide deletions at positions - 184/- 183 and - 182/- 181; and three previously identified SNPs (T-261G, C129T, G861C). Data were stratified by ethnicity and pooled Relative Risk was calculated for combined alcohol abuse and dependence cases and controls, and also for combined cocaine abuse and dependence cases and controls. No significant differences between cases and controls were found.     

Genetic polymorphisms of viral infection-associated Toll-like receptors in Chinese population

Toll-like receptors (TLRs) play a pivotal role in an innate immunity system, which controls inflammation responses and further instructs development of adaptive immunity. We enrolled 250 Han Chinese in Taiwan screening for the single nucleotide polymorphisms (SNPs) in TLRs associated with viral infection, including TLR2, TLR3, TLR4, TLR7, TLR8, and TLR9. The 6 SNPs not hitherto identified in Chinese populations, including TLR3 1377 C>T, TLR3 -7 C>A, TLR7 Gln11Leu, TLR7 IVS1+1817 G>T, TLR8 Met1Val, and TLR8 -129 G>C, had minor allele frequencies of 38%, 23%, 22.3%, 3%, 16.0%, and 16.0%, respectively. The frequencies of 2 common SNPs, TLR9, -1486 T>C and 2848 G>A, were 28% and 44%, respectively. As compared with other ethnic populations, Chinese displayed an opposite allele frequency of TLR8 Met1Val and TLR8 -129 G>C to Caucasians and African Americans. In addition, TLR2 Arg677Try, TLR2 Arg753Gln, TLR4 Asp299Gly, and TLR4 Thr399Ile that were apparent in approximately 10% of Caucasians were not detected in Chinese. In conclusion, obvious ethnic differences in TLR polymorphisms may in part reflect the ethnic diversity of host viral susceptibility.