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 between IL-10 gene polymorphisms and CARD15/NOD2 gene mutations. METHODS： A cohort of 205 Spanish unrelated patients with Crohn＇s disease recruited from a single center was studied. All patients were rigorously phenotyped and followed-up for at least 3 years （mean time, 12.5 years）. The clinical phenotype was established prior to genotyping. RESULTS： The correlation of genotype-Vienna classification groups showed that the Ueocolonic location was significantly associated with the -1082G allele in the NOD2/CARD15 mutation-positive patients （RR = 1.52, 95%CI, 1.21 to 1.91,P= 0.008）. The multivariate analysis demonstrated that the IL-10 G14 microsatellite allele in the NOD2/CARD15 mutation positive patients was associated with two risk factors, history of appendectomy （RR = 2.15, 95%CI = 1.1-4.30, P= 0.001） and smoking habit at diagnosis （RR= 1.29, 95%CI= 1.04-4.3, P= 0.04）. CONCLUSION： In Spanish population from Madrid, in CD patients carrying at least one NOD2/CARD15 mutation, the -1082G allele is assodated with ileocolonic disease and the IL-IOG14 microsatellite allele is associated with previous history of appendectomy and smoking habit at diagnosis. These data provide further molecular evidence for a genetic basis of the clinical heterogeneity of CD.