title: MHC class I chain-related gene A-A5.1 allele is associated with ulcerative colitis in Chinese population.
abstract: The human MHC class I chain-related gene A (MICA) plays a role in regulating protective responses by intestinal epithelial Vdelta1 gamma delta T cells and the polymorphism of MICA were reported to be related to several autoimmune diseases. The present study aimed to investigate the association of the microsatellite polymorphisms of TM region of MICA gene with the susceptibility to ulcerative colitis (UC) in Chinese population. The microsatellite polymorphisms of the MICA were genotyped in unrelated 86 Chinese patients with UC and 172 ethnically matched healthy controls by a semiautomatic fluorenscently labelled PCR method. All the subjects were the Chinese with Han nationality. The frequency of MICA-A5.1 homozygous genotype and A5.1 allele were significantly increased in UC patients compared with healthy controls (22.1%versus 7%, P = 0.0009, Pc = 0.0126, OR = 3.781, 95%CI: 1.738-8.225 and 30.2%versus 17.4%, P = 0.0014, Pc = 0.007, OR = 2.051, 95%CI: 1.336-3.148, respectively). Adjusted the effects of gender and age at onset, MICA-A5.1 homozygous genotype and A5.1 allele were also increased in the UC patients. Moreover MICA-A5.1 allele was significantly increased in frequency in the female UC patients (38.2%versus 21.0%, P = 0.0095, Pc = 0.0475, OR = 2.326, 95%CI: 1.234-4.382). Logistic regression analysis also revealed that gender was independently associated with UC patients carried MICA-A5.1 allele (P = 0.046, OR (male) = 0.511, 95% CI: 0.264-0.987). Although the UC patients with extensive colitis (32.5%versus 17.4% in the healthy controls, P = 0.005, Pc = 0.025) and the UC patients with extraintestinal manifestations (36%versus 17.4% in the healthy controls, P = 0.0039, Pc = 0.0195) were more likely to carry the MICA-A5.1 allele, EIMs was associated with extent of disease (P < 0.0001, OR (with EIMs) = 3.511, 95% CI 1.747-7.056) and MICA-A5.1 allele was not associated with UC patients with extensive colitis or with EIMs in the logistic regression analysis. Therefore, the MICA-A5.1 homozygous genotype and A5.1 allele were closely associated with UC and the MICA-A5.1 allele was positively associated with the female UC patients in Chinese population.
authors.affiliation: Department of Gastroenterology, Renmin Hospital, Wuhan, Peoples Republic of China.
authors.forename: Yijuan
authors.initials: Y
authors.lastname: Ding
authors.forename: Bing
authors.initials: B
authors.lastname: Xia
authors.forename: Min
authors.initials: M
authors.lastname: Lü
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jin
authors.initials: J
authors.lastname: Li
authors.forename: Mei
authors.initials: M
authors.lastname: Ye
authors.forename: Hesheng
authors.initials: H
authors.lastname: Luo
authors.forename: Jieping
authors.initials: J
authors.lastname: Yu
authors.forename: Xiaolian
authors.initials: X
authors.lastname: Zhang
authors.forename: Jingquan
authors.initials: J
authors.lastname: Tan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D002681:China / Q000453:epidemiology; D003093:Colitis, Ulcerative / Q000453:epidemiology / Q000235:genetics* / Q000276:immunology; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D005838:Genotype; D015395:Histocompatibility Antigens Class I / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics / Q000276:immunology; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics / Q000276:immunology; D017678:Sex Distribution
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A