A sequence variant on 17q21 is associated with age at onset and severity of asthma

A sequence variant (rs7216389-T) near the ORMDL3 gene on chromosome 17q21 was recently found to be associated with childhood asthma. We sought to evaluate the effect of rs7216389-T on asthma subphenotypes and its correlation with expression levels of neighboring genes. The association of rs7216389-T with asthma was replicated in six European and one Asian study cohort (N=4917 cases N=34 589 controls). In addition, we found that the association of rs7216389-T was confined to cases with early onset of asthma, particularly in early childhood (age: 0–5 years OR=1.51, P=6.89·10⁻⁹) and adolescence (age: 14–17 years OR=1.71, P=5.47·10⁻⁹). A weaker association was observed for onset between 6 and 13 years of age (OR=1.17, P=0.035), but none for adult-onset asthma (OR=1.07, P=0.12). Cases were further stratified by sex, asthma severity and atopy status. An association with greater asthma severity was observed among early-onset asthma cases (P=0.0012), but no association with sex or atopy status was observed among the asthma cases. An association between sequence variants and the expression of genes in the 17q21 region was assessed in white blood cell RNA samples collected from Icelandic individuals (n=743). rs7216389 associated with the expression of GSDMB and ORMDL3 genes. However, other sequence variants showing a weaker association with asthma compared with that of rs7216389 were more strongly associated with the expression of both genes. Thus, the contribution of rs7216389-T to the development of asthma is unlikely to operate only through an impact on the expression of ORMDL3 or GSDMB genes.     

Cat exposure in early life decreases asthma risk from the 17q21 high-risk variant

1. Download high-res image (153KB)
2. Download full-size image

     

Association between ADAM33 polymorphisms and adult asthma in the Japanese population

Background ADAM33, a member of the ADAM (a disintegrin and metalloprotease) family, is a putative asthma susceptibility gene recently identified by positional cloning. It is important to know whether the association exists in ethnically diverse populations. Objective To assess whether genetic functional variants of ADAM33 relate to the susceptibility or some phenotypes in adult patients with bronchial asthma in a Japanese population. Methods We searched for single nucleotide polymorphisms (SNPs) in ADAM33 by PCR‐directed sequencing and identified 48 SNPs. Fourteen SNPs were selected with regard to the LD pattern, and genotyped by Taq‐Man and PCR–RFLP methods. We conducted an association study of ADAM33 with 504 adult asthmatic patients and 651 controls, and haplotype analyses of related variants were performed. Results Significant associations with asthma were found for the SNPs T1 (Met764Thr), T2 (Pro774Ser), S2 and V?3 (with the lowest P‐value for T1, P=0.0015; OR 0.63). We analysed the haplotype using these four polymorphisms, and found a positive association with haplotype CCTG (P=0.0024). Conclusion Our results replicate associations reported recently in other ethnic populations, and suggest that the ADAM33 gene is involved in the development of asthma through genetic polymorphisms.     

The polymorphisms of interleukin 17A (IL17A) gene and its association with pediatric asthma in Taiwanese population

Background:  The interleukin 17A ( IL17A ) gene, located on chromosome 6p and linked to asthma phenotype, is a highly potential candidate gene conferring asthma susceptibility. The purpose of this study was to investigate the genetic association between single nucleotide polymorphisms (SNPs) of IL17A and asthma in Taiwanese children.
Methods:  We selected and performed genotyping on nine SNPs that encompass the genomic region of IL17A in Taiwanese children with or without asthma. A total of 1939 subjects containing 1027 subjects in testing group and 931 subjects in validation group were recruited in this study.
Results:  After Bonferroni correction, SNP rs8193036 was found to have a weak association ( P  = 0.0074 × 9 = 0.066) in genotype frequency test. This association was confirmed by validation group. Logistic regression adjusted allergy comorbidity and gender showed a slightly weaker association.
Conclusions:  The results indicated an independent role of IL17A promoter polymorphism rs8193036 in the association with pediatric asthma in Taiwanese population.     

TIM-4基因多态性与湖北地区汉族人群支气管哮喘易感性的研究

目的 探讨T细胞免疫球蛋白域及黏蛋白域蛋白-4(T cells immunoglobulindomain andmucindomain protein-4,TIM-4)基因外显子2区Lys65Lys(G/A)、外显子9区Val1365Met(G/A)的单核昔酸多态性(SNP)与湖北地区汉族人群支气管哮喘易感性的关系.方法 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)的方法对湖北地区185例哮喘患者和162例健康者TIM-4基因外显子2区Lys65Lys(G/A)、外显子9区Vai365Met(G/A)的多态性进行分析,计算基因型和等位基因频率.结果 (1)湖北地区汉族人群健康者TIM-4基因外显子2区Lys65Lys(G/A)位G/G、G/A、A/A基因型频率分别为0.840、0.160、0,而哮喘人群其频率分别为0.859、0.141、0,其基因型和等位基因型频率与对照组相比差异均无统计学意义(P=0.603,P=0.618);(2)本试验未检测到TIM-4外显子9区Va1365Met(G/A)的多态性.结论 湖北地区汉族人群TIM-4基因外显子2区Lys65Lys(G/A)存在单核苷酸多态性变异,但该位点的变异与湖北地区汉族人群支气管哮喘易感性无关;TIM-4基因外显子9区Va1365Met(G/A)在湖北地区汉族人群中未发现单核苷酸多态性.     

Interleukin-17A and -17F single nucleotide polymorphisms associate with susceptibility of asthma in Chinese Han population

Interleukin 17 (IL-17) plays important roles in the progression of asthma. Genetic variants in the Il-17 may influence the immunopathogenesis of many diseases. Many studies have investigated the relevance of IL-17 polymorphism with cancers or immune diseases, including asthma. In this study, single nucleotide polymorphisms (SNPs) of IL-17 were explored by PCR-RFLP and verified by sequencing method. The frequencies of genotypes and alleles were analyzed. Haplotypes were analyzed with the SHEsis online program. The relationship between the genotypes of SNPs and IgE level was also investigated. The False Discovery Rate (FDR) correction was performed (P-adjusted?<?0.05). The frequencies of A allele, GA and (GA?+?AA) genotype of rs3748067 were significantly higher in asthma patients. As for rs763780, the C allele in patients was more frequent than healthy controls. In addition, we found C carriers (CT?+?CC) were significantly higher in asthma patients. We further found that the haplotype CT for IL-17F (rs763780/rs2397084) was associated with an increased susceptibility of asthma, but this association did not survive after FDR correction. The level of serum total IgE in mutant group (GA?+?AA) of rs3748067 was significantly higher than the wild genotype (GG) group and control group. These results suggested that IL-17 SNPs, but not haplotypes may be associated with the susceptibility of asthma in Chinese Han population from central China.     

eotaxin-3基因多态性与变应性哮喘的相关性

目的研究eotaxin-3基因多态性与变应性哮喘的相关性。方法用聚合酶链反应-单链构象多态性-四引物聚合酶链反应-限制性酶切的方法对湖北地区汉族成人eotaxin-3＋77C／T和＋2497T／G单核苷酸多态性与哮喘易感性、嗜酸性粒细胞（eosinophil，EOS）计数以及血浆总IgE水平的相关性进行了分析。结果eotaxin-3＋2497位哮喘组与对照组G等位基因的频率，哮喘组IgE浓度及EOS数量差异有统计学意义，P值分别为0．01l、0．021和0．029；＋77位哮喘组与对照组T等位基因的频率，哮喘组IgE浓度差异无统计学意义，P值分别为0．824和0．473；＋77位哮喘组EOS数量差异有统计学意义，P值为0．044。结论eotaxin-3＋2497T／G多态性与哮喘易感性、EOS数量及IgE水平相关，＋77位C／T基因多态性与哮喘EOS数量相关。     

基于家系的Tim-3基因多态性与儿童变应性哮喘的关联研究

目的 以家系资料为基础,利用遗传不平衡原理探讨染色体5q33.2区Tim-3基因启动子两个多态性位点rs10053538和rs10515746与中国湖北地区汉族儿童变应性哮喘的关系.方法 应用限制性片段长度多态性技术结合测序方法,分析了118个儿童变应性哮喘核心家系Tim-3基因rs10053538和rs10515746的基因型;采用基于家系的关联分析方法,包括单体型相对风险分析(HRR)和传递不平衡检验(TDT),分析基因分型数据;应用Transmit软件构建单体型并进行单体型关联分析.结果 118个核心家庭HRR分析显示Tim-3基因启动子区两个多态性位点rs10053538和rs10515746不使病人具有更高的发病风险(X2=2.430,P>0.05;x2=1.368,P>0.05).118个满足经典TDT分析的核心家庭中,杂合子父母传递给患病子代的等位基因频率不比预期值高(x2=2.042,P>O.05;x2=0.750,P>O.05).Transmit双位点单体型分析也未见父母传递给子女各个单体型的观察值和期望值有明显差异(P>O.05).结论 中国湖北地区汉族人群中,Tim-3基因启动子区两个多态性位点rs10053538和rs10515746与儿童变应性哮喘不具有相关性.     

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。     

Eotaxin-1基因多态性与过敏性疾病相关性的研究进展

目前,过敏性疾病发病率不断上升,但其发病机制尚不明确,嗜酸性粒细胞(Eos)组织浸润是过敏性疾病的典型特征,嗜酸性粒细胞趋化因子(Eotaxin)作为Eos强有力的趋化因子,通过特异性结合Eos表面的CCR3受体趋化血液中的Eos到相应的靶器官,并活化Eos,引起组织损伤,其中Eotaxin-1对过敏性疾病具有意义.因而研究Eotaxin-1基因单核苷酸多态性(SNP)与过敏性疾病如哮喘、特应性皮炎、鼻息肉、嗜酸性粒细胞性食管炎的相关性具有现实意义.     

IL-4和IL-4受体基因多态性与成人变应性哮喘的关系

目的　研究白细胞介素 4 (IL 4 )、IL 4受体α链的 2个基因多态性位点与中国成人变应性哮喘的关系。方法　采用病例对照方法 ,用聚合酶链反应 限制性片段长度多态性方法 (PCR RFLP)对IL 4启动子区C - 5 89T和IL 4Rα链Q5 76R进行基因分型。结果　IL 4C - 5 89T与中国成人变应性哮喘无关 ,然而 ,变应性哮喘组IL 4Rα链 5 76R R频率显著性高于对照组 (χ2 =9.36 9,P <0 .0 1;OR =3.797) ,且与血浆高IgE相关。结论　IL 4Rα链 5 76R R基因型是中国成人变应性哮喘的基因危险因子     

Association between interleukin-1 receptor antagonist gene and asthma-related traits in a German adult population

Background:  A recent study in German and Italian families associated variants in the interleukin-1 receptor antagonist (IL1RA) gene with asthma. The aim of the present study was to further investigate the role of single nucleotide polymorphisms (SNPs) in the IL1RA gene in the development of atopy and lifelong asthma in a population-based study.
Methods:  DNA samples from the German centres of the European Community Respiratory Health Survey were analysed for genetic variants in the IL1RA gene and the development of asthma, atopy and bronchial hyperreactivity.
Results:  Carriers of the rare G allele of SNP rs447713 had a significantly increased risk of developing asthma ( P  = 0.0013) and allergic sensitization ( P  = 0.0119). Carriers of the rare C allele of SNP rs3087271 had an increased risk of asthma ( P  = 0.0227) and high immunoglobulin E (IgE) levels ( P  = 0.0232). A haplotype built from eight SNPs in the IL1RA gene (A-C-A-G-A-C-G-A) was associated with a higher prevalence of asthma ( P  = 0.007) and high total IgE ( P  = 0.02). Bronchial hyperreactivity was positively associated with the haplotype A-C-G-G-A-C-G-C ( P  = 0.02) and negatively with the A-C-G-G-A-C-T-C ( P  = 0.03).
Conclusion:  A previously described association between IL1RA and asthma in families could be reproduced in a population-based sample. The genetic variants of IL1RA gene do not to seem to affect asthma alone, but to act as modulators of asthma-related traits as well, where different haplotypes drive the development of different phenotypes.     

<Emphasis Type="Italic">ADAM33 </Emphasis>polymorphisms are associated with aspirin-intolerant asthma in the Japanese population

Multiple single nucleotide polymorphisms (SNPs) within ADAM33 have been reported to be associated with asthma and bronchial hyper-responsiveness in Caucasian populations. We examined whether these SNPs contribute to a predisposition to asthma, especially aspirin-intolerant asthma (AIA), in the Japanese population. Ten polymorphic sites (ST+4, ST+7, T1, T2, T+1, V-3, V-2, V-1, V4, V5) were genotyped in 102 AIA patients, 282 aspirin-tolerant asthma (ATA) patients and 120 control (CTR) subjects by direct sequencing. Haplotype frequencies were estimated by the expectation-maximization method. Differences in allele and haplotype frequencies among phenotypes were analyzed by the chi-square and permutation tests. ST+7, V-1 and V5 sites in the AIA group were significantly different from those in the ATA group (P=0.034–0.004) and from those in the CTR group (P=0.019–0.002). Haplotypes at three sites (ST+7, V-1, and V5) were significantly different in frequency between the AIA and ATA (P=0.008) or CTR (P=0.001) groups. Sequence variations in ADAM33 are likely to correlate with susceptibility to AIA in the Japanese population. The authors declare that they have no conflict of interest.     

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。