NOD2/CARD15与克罗恩病相关性研究进展

克罗恩病(CD)是一种常见的炎症性肠病,是环境因素作用于易感个体产生的肠道慢性非特异性炎症。其发病机制尚未完全明了。NOD2/CARD15是目前确认的第一个与CD相关的基因,通过介导凋亡,调节免疫等多种途径参与CD的发病。本文就NOD2/ CARD15与CD的研究进展作一综述。     

NOD2/CARD15基因突变与中国人克罗恩病相关性的研究

背景：近年多项研究证明NOD2／CARD15基因序列的单核苷酸多态性（SNP）与西方白种人克罗恩病（CD）明显相关．其中3个SNP（R702W、G908R和3020ins C）与CD的相关性尤为显著。目的：探讨NOD2／CARD15基因SNP与中国人CD发病的相关性及其与CD临床特点的关系。方法：选取临床资料完整的CD患者48例、溃疡性结肠炎（UC）患者和健康对照者各50例，提取人血白细胞基因组DNA，经聚合酶链反应（PCR）扩增NOD2基因全部12对外显子，纯化后直接测序，根据结果分析其突变与CD病变特点的关系。结果：CD组、UC组和健康对照组均未检出3个西方人常见的NOD2／CARD15基因多态性位点。CD组的P268S突变率显著高于UC组和健康对照组（P〈0．05）。5例P268S突变的CD患者病变均位于回肠（P〈0．01），4例发病年龄≤20岁（P〈0．01），且均并发肠腔狭窄（P〈0．01）。结论：中国人CD患者中存在NOD2／CARD15基因P268S突变，且与患者的发病年龄、病变部位和并发症相关，有必要对其功能作进一步探讨。     

CARD15/NOD2基因多态性与克罗恩病发病的荟萃分析

克罗恩病（CD）是一种具有遗传背景的多因素疾病。位于第16号染色体上的CARD15／NOD2基因被确定为克罗恩病的易感基因，该基因是参与细胞凋亡调控的Apaf21／PCed4超家族成员之一，主要在单核巨噬细胞内表达。有研究证明，CARD15／NOD2基因上三个多态位点（R702W、G908R、3020sinC）与克罗恩病发病相关。为综合评价CARD15／NOD2基因序列单核苷酸多态性同克罗恩病发病的相关性，我们用荟萃分析方法对二者的关系进行综合定量再分析，探讨CARD15／NOD2基因多态性与克罗恩病发病的关系。     

NOD2/CARD15基因多态性与克罗恩病患者相关性研究

目的NOD2/CARD15基因是人类的第一个克罗恩病(CD)易感基因,其间的3个单核苷酸多态性(SNPs)与白种人CD有显著性相关,但与日本人无关。本研究旨在证实这3个SNPs是否与浙江地区人群的CD易感性有关。方法血样来自浙江地区32例CD患者,110例溃疡性结肠炎患者及292例健康对照者。通过PCRSSP方法直接检测野生型及NOD2/CARD15基因的3个多态性(Arg702Trp,Gly908Arg,Leu1007fsinsC)。结果没有发现1例CD患者纯合子或杂合子的SNPs突变,同样在溃疡性结肠炎患者和健康人中也未能检测到。结论本研究表明一些存在于特定人群的CD易感基因可能在其他人群中不存在,白种人CD患者相关的易感基因NOD2/CARD15常见的3个SNPs与浙江地区CD人群无关。     

克罗恩病的第一个易感基因,NOD2(CARD15)

炎症性肠病 (ＩＢＤ)具有遗传易感性 ,主要表现在家族聚集现象和双胎同胞的共患率[1] 。近年来 ,随着人类基因组和多基因疾病研究以及统计学方法的进展 ,相继发现ＩＢＤ的基因易感位点 ,证实ＩＢＤ的遗传易感性涉及多个基因位点[2 ] 。 1996年Ｈｕｇｏｔ等[3 ] 采用非参数连锁分析 (ｎｏｎｐａｒａｍｅｔｒｉｃｌｉｎｋａｇｅａｎａｌｙｓｉｓ,ＮＰＬ)法 ,对ＩＢＤ患病同胞 (ａｆｆｅｃｔｅｄｓｉｂｌｉｎｇｐａｉｒｓ,ＡＳＰ)进行基因组位点微卫星标记研究 ,发现克罗恩病 (ＣＤ)的易感位点位于第 16条染色体的着丝点附近 ,称为ＩＢＤ1位点 …     

NOD2／CARD15在克罗恩病发生发展中的作用

NOD2／CARD15是迄今为止发现的第一个克罗恩病（Crohn’s disease，CD）的易感基因。目前研究最为广泛的NOD2的三种主要变异为：R702W、G908R及L1007fs。其中以L1007fs与CD相关性最强，它通过干扰NF—κB途径参与CD的发生发展。NOD2变异还与CD的各种表型相关，包括发病年龄、病变部位、病情严重程度、纤维狭窄病变、手术时期、手术风险等。NOD2与CD的相关性在不同地区、不同人种之间亦存在着显著差异。通过对NOD2的研究将更好地揭示CD的发病机制及治疗方向。     

NOD2/CARD15基因R702W、G908R及L1007fs多态性与广西壮族人群炎症性肠病的相关性

目的:探讨我国广西壮族人群NOD2/CARD15基因R702W、G908R及L1007fs的遗传多态性与炎症性肠病的相关性.方法:分别收集2007-02/2010-10在广西地区无亲缘关系的壮族(n=70)和汉族(n=76)IBD患者及壮族(n=80)和汉族(n=84)正常对照者的肠黏膜组织.采用酚氯仿法提取各组织样本DNA,采用聚合酶链反应-限制性片段长度多态性分析(PCR-RFLP)方法对NOD2/CARD15基因R702W、G908R及L1007fs进行检测,统计基因型及等位基因频率,分析上述3个多态性位点与广西壮族人群炎症性肠病的相关性.结果:广西壮族和汉族IBD患者与正常对照者均未发现NOD2/CARD15基因R702W、G908R及L1007fs突变型基因型,所有多态性位点上的基因型全部为野生型纯合子,其基因型频率和等位基因频率分布在IBD患者和正常对照者中差异无统计学意义(P>0.05).结论:NOD2/CARD15基因R702W、G908R及L1007fs多态性与广西壮族人群炎症性肠病无明显相关性.     

CD第一个易感基因NOD2及其与CD易感性的研究进展

目前认为克罗恩病(CD)是遗传易感者受环境因素作用而发病,其发病符合多基因病的遗传规律[1],其遗传易感性主要表现在家族聚集现象及双胞胎共患率上[2].近年来,随着人类基因组计划的进展和多基因病研究及统计学方法的发展,已发现了人类CD的第一个易感基因-NOD2基因,现命名为CARD15基因,本文就NOD2基因及其与CD易感性的研究进展作一综述.     

Toll-like receptor 4 and NOD2／CARD15 mutations in Hungarian patients with Crohn＇s disease： Phenotype-genotype correlations

AIM: To determine common NOD2/CARD15 mutations and TLR4 D299G polymorphism in Hungarian patients with CD. METHODS: A total of 527 unrelated patients with CD (male/female: 265/262, age: 37.1 (SD 7.6) years) and 200 healthy subjects were included. DNA was screened for possible NOD2/CARD15 mutations by denaturing high-performance liquid chromatography (confirmed by direct sequencing). TLR4 D299G was tested by PCR-RFLP. RESULTS: NOD2/CARD15 mutations were found in 185 patients (35.1%) and in 33 controls (16.5%,P<0.0001). SNP8/R702W (10.8% vs 6%, P= 0.02), SNP13/3020insC (19.4% vs 5%, P<0.0001) and exon4 R703C (2.1% vs 0%, P= 0.02) mutations were more frequent in CD, while the frequency of SNP12/G908R was not increased. The frequency of TLR4 D299G was not different (CD: 9.9% vs controls: 12.0%). Variant NOD2/CARD15 allele was associated with an increased risk for CD (ORhet=1.71, 95%CI=1.12-2.6, P= 0.0001, ORtwo-risk alleles = 25.2, 95%CI =4.37- ,P<0.0001), early disease onset (carrier: 26.4 years vs non-carrier: 29.8 years, P=0.0006), ileal disease (81.9% (?) 69.5%, OR = 1.99, 95%CI = 1.29-3.08, P= 0.02, presence of NOD2/CARD15 and TLR4: 86.7% vs 64.8%), stricturing behavior (OR = 1.69,95%CI = 1.13-2.55, P= 0.026) and increased need for resection (OR=1.71, 95%CI: 1.13-2.62, P= 0.01), but not with duration, extra-intestinal manifestations, familial disease or smoking. TLR4 exhibited a modifier effect: age of onset in wt/TLR4 D299G carriers: 27.4 years vs NOD2mut/TLR D299G: 23 years (P = 0.06), in NOD2mut/wt: 26.7 years. CONCLUSION: These results confirm that variant NOD2/ CARD15 (R702W, R703C and 3020insC) alleles are associated with earlier disease onset, ileal disease, stricturing disease behavior in Hungarian CD patients. In contrast, although the frequency of TLR4 D299G polymorphism was not different from controls, NOD2/TLR4 mutation carriers tended to present at earlier age.     

NOD2/CARD15基因突变与克罗恩病的相关性研究进展

克罗恩病(CD)是炎症性肠病(IBD)的一种，其病因及发病机制仍不明确，大量证据表明是由遗传因素、环境因素自身免疫紊乱三者相互作用的结果，其中遗传易感因素在CD发病机制中起重要作用。其遗传易感性主要表现为家族聚集现象、单卵双生共患率及不同人群发病率、流行率差异较大。自2001年发病并证实人类CD第一个易感基因NOD2／CARD15以来，关于该基因突变与CD相关性研究已成为IBD研究领域的热点，本文就其研究进展作一综述。     

CARD15/NOD2 polymorphisms do not explain concordance of Crohn''s disease in Swedish monozygotic twins

BACKGROUND: CARD15/NOD2 polymorphisms are associated with Crohn's disease. There is a high concordance for disease and disease phenotype in monozygotic twin pairs with Crohn's disease. AIM: We studied CARD15/NOD2 polymorphisms in a Swedish, population-based cohort of monozygotic twins with Crohn's disease to assess whether these variants explain disease concordance. SUBJECTS AND METHODS: Twenty-nine monozygotic twin pairs (concordant n=9, discordant n=20) with Crohn's disease and 192 healthy controls were investigated for the CARD15/NOD2 variants Arg702Trp, Gly908Arg and Leu1007fsinsC. RESULTS: CARD15/NOD2 mutations were found in 5/38 (13%) twins with Crohn's disease, corresponding to a total allele frequency of 6.6%. Only 2/9 concordant twin pairs carried any of the variants and the remaining seven were wild type genotype. The total allele frequency was 4.4 times higher (95% confidence interval 1.0-21.5, p=0.06) in concordant twins than in discordant ones, 11.1% versus 2.5%. In healthy controls the total allele frequency was 2.6%. CONCLUSIONS: CARD15/NOD2 polymorphisms contribute but do not alone explain concordance of Crohn's disease in monozygotic twins and, at least in a Swedish population, other polymorphisms are required. The low occurrence of CARD15/NOD2 mutations in the study and other Northern European populations suggests that these variants are of less importance in Northern Europe.     

Polymorphisms in interleukin-10 gene according to mutations of NOD2/CARD15 gene and relation to phenotype in Spanish patients with Crohn＇s disease

AIM:To examine the contribution of interleukin-10(IL-10)gene polymorphisms to Crohn's disease(CD)phenotype,and the possible genetic epistasis betweenIL-10 gene polymorphisms and CARD15/NOD2 genemutations.METHODS:A cohort of 205 Spanish unrelated patientswith Crohn's disease recruited from a single centerwas studied.All patients were rigorously phenotypedand followed-up for at least 3 years(mean time,12.5years).The clinical phenotype was established prior togenotyping.RESULTS:The correlat on of genotype-Viennaclassification groups showed that the ileocolonic locationwas significantly associated with the-1082G allele in theNOD2/CARD15 mutation-positive patients(RR=1.52,95%CI,1.21 to 1.91,P=0.008).The multivariate analysisdemonstrated that the IL-10 G14 microsatellite allelein the NOD2/CARD15 mutation positive patients wasassociated with two risk factors,history of appendectomy(RR=2.15,95%CI=1.1-4.30,P=0.001)and smokinghabit at diagnosis(RR=1.29,95%CI=1.04-4.3,P=0.04).CONCLUSION:In Spanish population from Madrid,inCD patients carrying at least one NOD2/CARD15 mutation,the-1082G allele is associated with ileocolonic disease and the IL-10G14 microsatellite allele is associated withprevious history of appendectomy and smoking habit atdiagnosis.These data provide further molecular evidencefor a genetic basis of the clinical heterogeneity of CD.     

Prevalence of mutations of the NOD2/CARD15 gene and relation to phenotype in Spanish patients with Crohn disease

Background: We assessed the prevalence of R702W, G908R, and L1007fs coding mutations in the NOD2/CARD15 gene and the genotype–phenotype relation in Spanish patients with Crohn disease. Methods: A cohort of 204 unrelated patients with Crohn disease and 140 healthy controls were studied. The phenotype was established before commencement of genotyping. Genotyping of the R702W, G908R, and L1007fs gene polymorphisms of NOD2/CARD15 was performed by two independent laboratories using different techniques. In the case of discordant results, specific sequencing of DNA strands was performed. Results: At least one mutation was present in 32.8% of patients compared to 10.7% in controls (OR?=?4.08, 95% CI 2.21 to 7.50). In patients with Crohn disease, the frequency of R702W, G908R, and L1007fs carriers was 13.7%, 8.3%, and 14.2%, respectively. Compound heterozygotes and homozygotes occurred in 3.4% and 2.9% of patients and in none of the controls. The correlation of genotype–Vienna classification showed a significant association with ileal disease (RR?=?1.61, 95% CI 1.21–2.15, P?=?0.001) and an inverse association with colonic localization (RR?= 0.29, 95% CI 0.11–0.80, P?=?0.007). There was a significant association between G908R carriership and previous appendectomy, surgical interventions, and stricturing behavior. A gene‐dosage effect on phenotypic characteristics was not observed. Conclusions: In a Spanish population from Madrid, mutations of the NOD2/CARD15 gene were a marker of susceptibility to Crohn disease and were associated with ileal disease. Carriers of the G908R mutation showed a stricturing disease behavior, history of appendectomy, and surgical interventions over the course of the disease.     

Clinical significance of NOD2/CARD15 and Toll-like receptor 4 gene single nucleotide polymorphisms in inflammatory bowel disease

AIM： To evaluate the role of genetic factors in the pathogenesis of Crohn＇s disease （CD） and ulcerative colitis （UC）, we investigated the single nucleotide polymorphisms （SNPs） of NOD2/CARD15 （R702W, Gg08R and L1007finsC）, and Toll-like receptor 4 （TLR4） genes （D299G and T399I） in a selected inflammatory bowel disease （IBD） population coming from Southern Italy. METHODS： Allele and genotype frequencies of NOD2/ CARD15 （R702W, Gg08R and L1007finsC） and TLR4 （D299G and T399I） SNPs were examined in 133 CD patients, in 45 UC patients, and in 103 healthy controls. A genotype-phenotype correlation was performed. RESULTS： NOD2/CARD15 R702W mutation was significantly more frequent in CD （9.8%） than in controls （2.4%, P = 0.001） and in UC （2.3%, P = 0.03）. No significant difference was found between UC patients and control group （P 〉 0.05）. In CD and UC patients, no significant association with G908R variant was found. L1007finsC SNP showed an association with CD （9.8%） compared with controls （2.9%, P = 0.002） and UC patients （2.3%, P = 0.01）. Moreover, in CD patients, G908R and L1007finsC mutations were significantly associated with different phenotypes compared to CD wild-type patients. No association of IBD with the TLR4 SNPs was found in either cohort （allele frequencies： D299G-controls 3.9%, CD 3.7%, UC 3.4%, P 〉 0.05; T399I-controls 2.9%, CD 3.0%, UC 3.4%, P 〉 0.05）. CONCLUSION： These findings confirm that, in our IBD patients selected from Southern Italy, the NOD2/ CARD15, but not TLR4 SNPs, are associated with increased risk of CD.     

Identification of NOD2/CARD15 mutations in Malaysian patients with Crohn's disease

OBJECTIVE: The NOD2/CARD15 gene has been identified as an important susceptibility gene for Crohn's disease (CD) but the three common disease predisposing mutations (DPM) found in developed countries have not been identified in Asian populations. The aim of our study was to look for the DPM in our multiracial population and to discover whether there were any differences in the three major ethnic groups; Malay, Chinese and Indian. METHODS: Blood samples from consecutive CD patients and healthy controls were obtained and analyzed for the three common mutations (R702W, G908R, 1007fs) but in addition to this, we also looked for the SNP5 and JW1 variants which are associated with CD in Ashkenazi Jews. A polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) technique was used to identify the mutations, which was confirmed by sequencing. The baseline socio‐demography and clinical characteristics of the CD patients were recorded. RESULTS: Overall 45 patients (three Malays, 15 Chinese, 26 Indians and one other) with confirmed CD and 300 controls were recruited. The three common DPM were not observed in either the CD patients or the controls. Neither the SNP5 nor the JW1 mutation was found in any of the controls. However, the SNP5 mutation was identified in six (13.3%) Indian CD patients and the JW1 mutation in eight CD patients who are different from those carrying the SNP5 mutation: one Malay (33.3%), two Chinese (13.3%), one other (Portuguese) and four Indians (15.4%). The presence of SNP5 was strongly associated with CD in the Indian population and that of JW1 was strongly associated with CD overall and in each of the major ethnic groups. There was a trend towards a younger age of onset and stricturing disease in patients carrying the JW1 mutation. CONCLUSION: These findings suggest the presence of novel DPM in the NOD2/CARD15 gene in Asian patients with CD.     

P268S突变型NOD2/CARD15真核表达载体的构建及其体外表达

背景：NOD2/CARD15基因序列单核苷酸多态性（SNP）与欧美人群的克罗恩病（CD）明显相关．其中R702W、G908R和3020insC3个SNP位点与CD的相关性尤为显著。而13本、韩国以及我国香港和浙江地区的研究均未发现上述3个SNP的改变，但最近研究发现了可能与中国人CD相关的P268S突变。目的：构建P268S突变型NOD2／CARD15真核表达载体和体外转染体系，为研究突变型NOD2／CARD15的功能提供实验基础。方法：应用定点诱变技术构建P268S突变型NOD2／CARD15真核表达载体，以阳离子脂质体介导体外转染技术瞬时转染人胚肾细胞HEK293T．以蛋白质印迹法和逆转录聚合酶链反应（RT—PCR）检测HEK293T细胞NOD2／CARD15的表达。结果：经克隆、酶切、测序证实获得P268S突变型NOD2／CARD15基因，突变载体转入HEK293T细胞后，NOD2／CARD15有效表达。结论：成功构建了P268S突变型NOD2／CARD15真核表达载体，阳离子脂质体是人胚肾细胞有效的体外转染体系。