Association of NOD2/CARD15 variants with Crohn's disease in a Greek population

OBJECTIVE: Single nucleotide polymorphisms in the NOD2/CARD15 gene have recently been shown to be associated with Crohn's disease (CD), but whether this susceptibility extends to all ethnic groups and geographic areas remains unknown. The aim of the present study was to evaluate the NOD2/CARD15 mutations in Greek patients with CD. METHODS: Individuals were genotyped for three NOD2/CARD15 mutations: R702W, G908R and L1007fsinsC. Blood samples were obtained from 120 patients with CD, 85 patients with ulcerative colitis, and 100 unrelated healthy controls. RESULTS: Mutations in NOD2/CARD15 were observed with significantly greater frequency in CD patients (98/120, 81.7%) than in ulcerative colitis patients (40/85, 47%) (P < 0.0001) or in healthy individuals (21/100, 21%) (P < 0.0001). For CD patients, compared with controls, the odds were increased for carriage of the R702W (odds ratio, 12.25) and less for the G908R (odds ratio, 5.2) and L1007fsinsC (odds ratio, 3.9) mutations. The age of onset of CD was lower in Greek mutation carriers as compared with non-carriers of Greek origin (28.2 +/- 14.6 years versus 34 +/- 12.3 years, respectively; P = 0.036). Additionally, the frequency of NOD2/CARD15 mutations was increased in ileitis or ileocolitis compared with non-ileal disease. CONCLUSIONS: The NOD2/CARD15 mutations are risk factors for CD in Greece, they appear to predict an earlier age of onset and are associated particularly with ileitis or ileocolitis.     

NOD2/CARD15 disease associations other than Crohn's disease

At this moment, few confirmed associations between NOD2 mutations and diseases other than Crohn's disease (CD) and Blau syndrome (BS) have been reported, but research is ongoing in several fields where a genetic susceptibility factor and/or a role for the innate immune system is suspected. Whether the Crohn's-associated CARD15 mutations lead to a loss or gain of function of the NOD2 receptor is subject to controversy, and by which mechanisms this change in function might increase the susceptibility to CD is still under investigation. The possible involvement of NOD2/CARD15 in the pathogenesis of certain diseases with already (partially) unraveled pathophysiologic mechanisms might contribute to our further understanding of NOD2/CARD15 and its function in CD. We review studies on the association of CARD15 variants with diseases other than CD. The association of NOD2/CARD15 mutations with CD and BS, and possibly also early onset sarcoidosis, suggests a role for the gene in the development of granulomata and granulomatous diseases, possibly by inappropriate activation of the immune system. The data from the oncology field suggest that this inappropriate activation might even lead to uncontrolled proliferation of certain cell types. The studies in allergic diseases and atopy are the largest so far, and the association of NOD2/CARDI5 mutations with atopic phenotypes might be an indication that CARD15 also plays a role in the Th2 pathway. Finally, transplantation studies indicate that the genetic background of a patient should be taken into account when considering hematopoietic stem cell transplantation, given the increased risk of mortality and graft versus host disease observed. Whether NOD2 variants are also associated with an increased risk for infections and sepsis in patients receiving immunosuppressive therapies is unclear.     

NOD2/CARD15 gene polymorphisms in Crohn's disease: a genotype- phenotype analysis

OBJECTIVES: Three recently identified NOD2/CARD15 mutations have been described associated with an increased susceptibility Crohn's disease (CD). Our aim was to examine the potential association of these NOD2 mutations with CD and different subsets of CD phenotypes in our population. METHODS: Two hundred and five well-defined CD patients from north-western France and 95 ethnically matched healthy controls were genotyped for mutations R702W, G908R and Leu1007insC by DNA sequencing. Allele and genotype frequencies of NOD2 variants were examined in the whole series of CD and in different subgroups of CD phenotypes defined by the clinical characteristics of the Vienna classification (age at diagnosis, location and behaviour) or by histological features (granuloma). RESULTS: Carriers of at least one NOD2/CARD15 variant were significantly more frequent in CD than in controls (38.0% versus 20.0%, P < 0.002), and the R702W allele was the most significant contributor to this NOD2 association with CD. Homozygotes and compound heterozygotes combined had a higher risk of CD (odds ratio = 12.0, P < 0.0026) than simple heterozygotes for any variant (odds ratio = 2.2, P < 0.013) compared with subjects with no variant. Univariate analysis revealed that carriage of at least one NOD2 mutation was significantly associated with ileal involvement (P < 0.03), and stricturing evolution (P < 0.0015). Granuloma was associated with an excess of the R702W allele (16.1% versus 8.0%, Pc < 0.035), and was correlated with a young age at diagnosis, whatever the NOD2/CARD15 genotype. Multivariate analysis demonstrated that carriage of NOD2/CARD15 mutants, especially R702W, was primarily and independently associated both with stricturing evolution of CD and the presence of granuloma. CONCLUSIONS: In our population, all NOD2/CARD15 mutant genotypes, especially compound heterozygosity, were found to increase the risk of CD, but R702W was the sole allele showing a significant association with CD. In addition, we confirm the positive and independent association of the R702W mutation with stricturing behaviour and describe a second one with the presence of granuloma.     

Clinical applications of NOD2/CARD15 mutations in Crohn's disease

The recent identification of the CARD15/NOD2 gene as a susceptibility locus for Crohn's disease represents an important step in the immunopathogenesis of inflammatory bowel disease. The gene explains about 20% of the genetic susceptibility CARD15 mutations are present in 30-50% of CD patients compared to 7-20% of healthy controls. The three risk alleles R702W, G908R and 1007fsInsC in NOD2 associated with susceptibility to Crohn's disease have demonstrated a remarkable amount of heterogeneity across ethnicities and populations, with regional variation across Europe. In non-Caucasian populations Crohn's disease continues to increase in incidence but this increase appears not to be a consequence of variation in NOD2. Genotype-phenotype analyses demonstrated an association of these mutations with ileum-specific disease and an increased incidence of the fibrostenotic phenotype. Although CARD15 variants do not predict response to the TNF alpha monoclonal antibodies, there are no data available on the possible influence of CARD15 mutations on response to other drugs. Screening for CARD15 mutations in order to identify high-risk individuals or to introduce an individualized disease management is therefore currently not recommended.     

NOD2/CARD15 variants are associated with lower weight at diagnosis in children with Crohn's disease

OBJECTIVES: NOD2/CARD15 variants have recently been shown to be associated with Crohn's disease (CD). No analysis of NOD2/CARD15 gene variants has so far been reported in pediatric patients. Therefore, our aim was to analyze NOD2/CARD15 gene variants in children with CD and to perform genotype-phenotype analyses. METHODS: We studied 101 children with CD and 136 healthy controls. Detailed phenotypic information was obtained from each patient. Patients were genotyped for the three NOD2/CARD15 variants R702W (single nucleotide polymorphism 8 [SNP8]), G908R (SNP12), and L1007fs (SNP13), and genotype-phenotype correlations were performed. RESULTS: We found 33 NOD2/CARD15 mutations in 29 of 101 patients (29%). The frequency of NOD2 variation was 31% in white (n=87) compared with 11% in controls (chi2=14; p=0.0001; OR=3.7; 95% CI=1.7-7.8). Four white patients but not control subjects were compound heterozygotes. NOD2/CARD15 variants were significantly associated with ileal disease (chi2=4.5; p=0.03; OR=5; 95% CI=0.9-35.9). Of the children with NOD2/CARD15 variants, 44% were < or =5th percentile for weight at diagnosis, whereas only 15% of children without mutations were < or =5th percentile (chi2=8.7; p=0.003; OR=4.5; 95% CI=1.4-14.4). Similar trends were observed for height but they did not reach statistical significance. CONCLUSIONS: Our results demonstrate that: 1) the three NOD2/CARD15 variants confer risk to CD in children; 2) NOD2/CARD15 variants are associated with ileal disease in children as in adults; and 3) NOD2/CARD15 variants are associated with lower weight percentiles at diagnosis in children and a tendency toward lower height percentile, suggesting an association between growth in children with CD.     

CARD15/NOD2 gene variants are associated with familially occurring and complicated forms of Crohn's disease

BACKGROUND: Variants of the caspase activating recruitment domain 15/nucleotide oligomerisation domain 2 (CARD15/NOD2) gene have been associated with susceptibility to Crohn's disease (CD). Aim: Our aim was to evaluate the allele frequencies of the CARD15 variants R702W, G908R, and 1007fs in Finnish inflammatory bowel disease (IBD) patients and to search for possible associations between CARD15 variants and occurrence of familial forms of IBD or complicated forms of CD. PATIENTS AND METHODS: We investigated 198 sporadic CD patients, 46 probands with familial CD, 27 CD probands from mixed IBD families, 99 unrelated patients with ulcerative colitis (UC), and 300 control individuals for the occurrence of the CARD15 gene variants R702W, G908R, and 1007fs. RESULTS: In CD patients, the allele frequencies for the rare variants of these polymorphisms were 3.3%, 0.6%, and 4.8% (total 8.7%), and the corresponding frequencies in healthy controls were 1.8%, 0%, and 1.7% (total 3.5%) (8.7% v 3.5%; p<0.01). In UC patients allele frequencies were comparable with those in controls. The frequency of the 1007fs polymorphism variant allele was significantly higher among all CD patients than in controls (4.8% v 1.7%; p<0.01) but there was no significant difference in allele frequencies between the CD and UC groups. The 1007fs allele frequency was higher in familial CD than in non-familial cases with CD (10.9% v 3.5%; p<0.01). There were no significant differences in the allele frequencies of the R702W and G908R polymorphisms between CD patients, UC patients, and controls. We found that 15.5% of CD patients, 9.1% of UC patients, and 6.7% of controls carried at least one of the CARD15 variants. In CD patients carrying at least one of the three NOD2 variants, the ileum was affected more often than in non-carrier CD patients (90% v 73%; p<0.05), they had stricturing or penetrating disease more often than non-carriers (88% v 56%; p<0.01), and they had an increased need for bowel surgery. CONCLUSIONS: The frequency of NOD2 gene variants was lower in genetically homogenous Finns than in other populations. The 1007fs variant was associated with CD. The occurrence of CARD15 variants predicted ileal location as well as stricturing and penetrating forms 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.     

NOD2/CARD15 gene variants are linked to failure of antibiotic treatment in perianal fistulating Crohn's disease

OBJECTIVES:  The Crohn's disease (CD) susceptibility gene, nucleotide-binding oligomerizetion domain 2 (NOD2)/caspase recruitment domain 15 (CARD15), is linked to the innate immune response associated with altered epithelial bacterial defense. Its relevance in antibiotic therapy of perianal fistulating CD remains elusive. The aim of the study was to explore systematically the association between NOD2/CARD15 variants and clinical response of perianal fistulas in patients using antibiotic therapy.
METHODS:  Fifty-two patients (median age 36 yr) with draining perianal fistulas were treated with ciprofloxacin (N = 49) or metronidazole (N = 3) for a median duration of 7 wk. Complete response was defined as the absence of any draining fistula despite gentle finger compression. Genotyping for NOD2/CARD15 variants and human beta (β)-defensin 2 (HBD-2) copies was performed by 5' nuclease assays (Applied Biosystems, Foster City, CA). The examiners and laboratory investigators were blinded. The Fisher exact test and Wilcoxon signed rank test were used for statistical analysis.
RESULTS:  Ciprofloxacin was discontinued in one patient due to diarrhea after 2 wk. Complete fistula response was observed in 13 of 39 patients with NOD2/CARD15 wild-type (33.3%) compared with none in patients carrying NOD2/CARD15 variants (0%, P = 0.02). The median number of HBD-2 gene copies between responders and partial/nonresponders was similar.
CONCLUSIONS:  The study result suggests a substantial contribution of NOD2/CARD15 to the antibiotic treatment outcome of perianal fistulating CD. NOD2/CARD15 variants may predispose to an altered intestinal microflora in perianal fistulas that is less responsive to antibiotic treatment.     

Crohn’s disease incidence evolution in North-western Greece is not associated with alteration of NOD2/CARD15 variants

AIM To assess the trends in the incidence of inflammatory bowel disease (IBD) over 23 years in the same area and to identify genetic factors related to incidence evolution.METHODS Patients with IBD arising from Northwestern Greece were systematically recorded through the 1983-2005 period. Trends in disease incidence and genetic patterns related to CARD15 variants were documented and correlated.RESULTS A total of 447 patients with IBD were recorded (23.5% Crohn's disease, 72.7% Ulcerative colitis and 3.8% indeterminate colitis). Mean annual incidence rates of CD and UC were 0.9/100000 (95% CI 0.1-1.7) and 2.7/100000 (95% CI 1.7-4.1) inhabitants,respectively. There was a statistically significant increase of CD incidence (P ＜ 0.01) during the study period, in contrast to the UC incidence. There were no statistical differences in CARD15 variants over the study period.CONCLUSION The incidence of CD in North-western Greece has risen disproportionately to that of UC in the 21st century. This is not related to alterations of genetic background though.     

NOD2／CARDl5基因突变与中国人克罗恩病相关性研究

背景NOD2／CARDl5基因是人类克罗恩病（Crohn＇s disease，CD）第一个易感基因，既往研究发现P268S可能与中国人CD发病及临床特征相关。目的本研究旨在证实P268S与中国人CD发病及其临床特征的相关性。方法血样来自临床确诊的50例CD患者，60例溃疡性结肠炎（ulcerativecolitis，uc）患者及100例健康体检者（healthy controls，HC）。提取人血白细胞基因组DNA．PCR扩增目的片段，PCR—RFLP发现突变位点，DNA测序证实突变位点。结果共有8例CD患者发现有P268S改变，而在UC患者和HC中分别发现2例和3例P268S改变，CD组明显高于UC和HC组（X^2=10．829，P=0．004），而UC组和HC组无明显差异。8例有P268S改变的CD患者临床特征包括病变多位于回肠．发病年龄轻（6例〈20岁），常并发肠腔狭窄而需手术治疗，中一重度患者比例高。结论P268S可能是NOD2/CARDl5基因中与中国人CD相关的SNP。P268S与CD患者发病年龄、病变部位及并发症及病情严重程度可能相关。     

NOD2/CARD15 , ATG16L1 and IL23R gene polymorphisms and childhood-onset of Crohn’s disease

AIM: To assess whether the polymorphisms of NOD2/ CARD15 , autophagy-related 16-like 1 (ATG16L1 ), and interleukin-23 receptor (IL23R ) genes play a more critical role in the susceptibility of childhood-onset than in adult-onset Crohn’s disease (CD). METHODS: Polymorphisms R702W, G908R, and 3020insC of NOD2/CARD15 ; rs2241880 A/G of ATG16L1 , and rs11209026 (R381Q) of IL23R gene were assessed in 110 childhood-onset CD, 364 adult-onset CD, and 539 healthy individuals. Analysis of polymorphisms R702W, G908R, ...     

NOD2/CARD15 does not influence response to infliximab in Crohn's disease

BACKGROUND & AIMS: NOD2/CARD15 was recently identified as the first gene underlying Crohn's disease (CD) susceptibility. Monoclonal antibodies to tumor necrosis factor (TNF)-alpha (infliximab) are a potent treatment for CD, with about 70% of patients responding. It is not clear which factors influence treatment outcome. We assessed whether variants in NOD2/CARD15 are predictive for differences in clinical response. METHODS: Two hundred forty-five CD patients (86 fistulizing, 159 luminal) receiving infliximab in an expanded access program were genotyped for the 3 main associated variants of NOD2/CARD15, without knowledge of the treatment response. Short-term clinical response was assessed at 4 weeks (refractory) or 10 weeks (fistulizing) after first infliximab infusion, and the mean duration of response was calculated. In a subgroup of patients, production of TNF in response to lipopolysaccharide (LPS) in mucosal biopsy tissue was also determined by means of immunoassay, and results were related to the different NOD2/CARD15 genotypes. RESULTS: In total, 32.6% of patients carried mutations in NOD2/CARD15 (18.8% R702W, 8.6% G908R, and 10.2% 1007fs) compared with 15% in controls (P < 0.001). Despite observed differences in TNF production in mucosal biopsy tissue, there was no relationship between the overall presence of a mutation in NOD2/CARD15 or of any of the mutations separately and short-term infliximab response or response duration. Furthermore, multivariate analysis could not identify clinical characteristics that, in combination with NOD2/CARD15 mutations, were associated with response to infliximab. CONCLUSIONS: In this cohort of CD patients, the frequency of NOD2/CARD15 mutations was significantly greater than that of healthy controls. However, NOD2/CARD15 was not predictive of treatment outcome with infliximab in CD.     

NOD2/CARD15 mutations in Croatian patients with Crohn's disease: prevalence and genotype-phenotype relationship

BACKGROUND: Crohn's disease (CD) is a chronic inflammatory disorder of the gastrointestinal tract with variations in localization and behaviour. Mutations in the NOD2/CARD15 gene on chromosome 16q have been implicated in the pathogenesis of the disease and three main sequence variants, all single nucleotide polymorphisms (SNPs), have been identified in North American and European populations. AIMS AND METHODS: As no data exist in the Croatian population, we consecutively collected a cohort of 136 CD patients and 91 healthy controls to determine the prevalence of NOD2/CARD15 mutations and their association with phenotypic expression of the disease. All patients and controls were genotyped for Arg702Trp (Hugot SNP8), Gly908Arg (Hugot SNP12), and Leu1007fsinsC (Hugot SNP13) and allele frequencies were compared between the Crohn's patients and controls. The correlation of NOD2/CARD15 genotypes with the phenotypic expression of Crohn's disease was further assessed by logistic regression analysis. RESULTS: NOD2/CARD15 variants were found in 38/136 CD patients (27.9%) compared to 10/91 (10.9%) healthy controls (P = 0.0022). Allele frequencies in patients with CD were 13.97%, 4.4% and 11.76%, respectively, for SNP8, 12 and 13, compared to 5.49%, 1.12% and 4.40% in controls (P = 0.041, P = 0.162, P = 0.055). Six CD patients carried double mutations and, remarkably, we identified two homozygous mutants amongst the healthy control group. Surgery over the course of the disease and a younger age at onset of the disease were significantly more frequent in patients who were carriers of NOD2/CARD15 mutations. CONCLUSIONS: This report on NOD2/CARD15 mutations in Croatian patients with CD demonstrates that this gene is also implicated in susceptibility to CD in the Croatian population. Phenotypic association showed a younger age at diagnosis and a higher need for surgery in patients carrying NOD2/CARD15 mutations. However, the prevalence is somewhat lower compared to other reports, likely due to a more prominent colonic inflammation.     

NOD2/CARD15 mutations and presence of granulomas in pediatric and adult Crohn's disease

OBJECTIVES: The etiology and mechanism leading to granuloma formation in patients with Crohn's disease (CD) are presently unknown. The first susceptibility gene to be identified as a risk factor for CD is the NOD2/CARD15 gene on Chromosome 16. Mutations in NOD2 could affect the intracellular response to bacterial products and may eventually lead to granuloma formation. The association between NOD2 and granulomas has not been previously explored. We evaluated a possible association between NOD2 mutations and granuloma formation, and compared the prevalence of granulomas in both pediatric and adult cohorts. METHODS: Patients were consecutively recruited through pediatric gastroenterology and adult gastroenterology programs. Patients were eligible if CD was confirmed, and they had undergone full colonoscopy with biopsy and/or surgical resection. Patients underwent genotyping for NOD2 disease-associated mutations. RESULTS: A total of 230 patients were enrolled into the study, of whom 169 patients met all inclusion/exclusion criteria (Group 1, 77 patients [age range 1-16 years]; Group 2, 92 patients [age range 17-68 years]). Surgical resection was performed more often in adults (P < 0.005), and gastroscopy was performed more frequently in children (P < 0.001). Granulomas were found in 34% of the patients studied. The prevalence of granulomas did not differ by age, age group, or gender. A disease-associated NOD2 mutation was found in 37.8% of patients. Granulomas were found in 39% of patients with NOD2 mutations compared with 31% of those without NOD 2 mutations (difference was not significant). In addition, no difference was noted for the specific mutations. CONCLUSIONS: We did not find any correlation between NOD2 mutations and granuloma formation. The cause of granulomas in CD remains elusive.     

Association of NOD2/CARD15 mutations with previous surgical procedures in Crohn's disease.

OBJECTIVE: The aim of this study is to assess the importance of NOD2/CARD15 gene mutations as prognostic factors for surgical indications in Crohn's disease. PATIENTS AND EXPERIMENTAL DESIGN: A total of 165 Crohn s disease patients were studied, considering previous surgery related to Crohn's disease. We analyzed for previous surgery in global procedures as well as separately for the two main surgical indications: ileal resection and fistula treatment. The need for appendectomy was also studied. All patients were genotyped for the three CARD15 mutations, and association studies were developed using Chi-square statistics and Fisher's exact test whenever appropriate. RESULTS: Carriers of the G908R or 1007fs mutation needed surgery more frequently, both for ileal resection and fistula repair. In contrast, appendectomy was not associated with CARD15 mutations. CONCLUSIONS: As previously reported in this population, the R702W mutation does influence parameters of disease or need of surgery. The need for Crohn's disease-related surgery is higher in carriers of the G908R or 1007fs CARD15 mutation in the Galician population. Nevertheless, the frequency of these mutations does not allow their use to predict the course of disease.     

Association of NOD2/CARD15 mutations on Crohn's disease phenotype in an Italian population

AIMS: To confirm the prevalence of NOD2/CARD15 mutations in Italian inflammatory bowel disease patients and to define the role of the different mutations on Crohn's disease phenotype. PATIENTS AND METHODS: A total of 177 patients with Crohn's disease and 92 patients with ulcerative colitis and 164 control participants were investigated for the presence of Arg702Trp, Gly908Arg and Leu1007fsinsC NOD2/CARD15 mutations. Allele frequencies in Crohn's disease and ulcerative colitis patients were compared with those observed in the control population. Genotype-phenotype correlations with the major clinical features were also established and estimated risks (odds ratio with 95% confidence interval) for the mutations were calculated by logistic regression and multiple correspondent analysis. RESULTS: Gly908Arg and Leu1007fsinsC mutations were significantly more frequent in Crohn's disease patients compared with healthy controls (P<0.01 and <0.003 respectively). Indeed, using a logistic regression model adding terms for age (differently distributed between cases and controls) and sex, a significantly increased risk of having Crohn's disease compared with healthy controls was found for all NOD2 mutations: Leu1007fsinsC (odds ratio=7.35; 95% confidence interval: 1.73-31.3), Gly908Arg (odds ratio=5.70; 95% confidence interval: 1.37-23.7) and Arg702Trp (odds ratio=2.45; 95% confidence interval: 1.10-5.47). As far as the genotype-phenotype correlations are concerned, by multivariate conditional logistic regression methods, we found a significant association between Gly908Arg mutations and familial history of inflammatory bowel disease, between Leu1007fsinsC mutations and appendectomy and between Arg702Trp mutations and fibrostenotic phenotype of Crohn's disease. A nonsignificant association between Arg702Trp variants and ileal disease was also found (odds ratio=8, 95% confidence interval: 0.99-64.9). CONCLUSIONS: The results of the study confirm a significant association of CARD15 gene mutations in our Italian Crohn's disease population and the impact of different NOD2/CARD15 mutations on specific disease phenotypes.     

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。