The association between vitamin D receptor polymorphisms and serum 25-hydroxyvitamin D levels with ulcerative colitis in Chinese Han population

• Published in: Clinics and research in hepatology and gastroenterology 2017-02, Vol.41 (1), p.110-117
• Main Authors: Zheng, Shu-zi, Zhang, Da-guan, Wu, Hao, Jiang, Li-jia, Jin, Jie, Lin, Xiu-qing, Ding, Ran, Jiang, Yi
• Format: Article
• Language: English
• Subjects: Adult; Alleles; Asian Continental Ancestry Group - statistics & numerical data; Case-Control Studies; China - epidemiology; Colitis, Ulcerative - ethnology; Colitis, Ulcerative - genetics; Female; Gastroenterology and Hepatology; Genotype; Humans; Internal Medicine; Male; Middle Aged; Polymorphism, Single Nucleotide - genetics; Receptors, Calcitriol - genetics; Vitamin D - analogs & derivatives; Vitamin D - blood; Vitamin D - genetics
• ISSN: 2210-7401; 2210-741X
• DOI: 10.1016/j.clinre.2016.09.001

Summary There is now growing evidence suggesting that Vitamin D is playing a critical role in modulating the innate and adaptive immune responses. Several polymorphisms have been identified in the vitamin D receptor ( VDR ) gene but their association with ulcerative colitis (UC) susceptibility remained controversy. In the current study, we examined the association between VDR polymorphisms and serum level of 25-hydroxyvitamin D [25(OH)D] with UC in Chinese Han population. Polymorphisms of FokI (rs2228570)/BsmI (rs1544410)/ApaI (rs7975232)/TaqI (rs731236) in the VDR gene were assessed in a case–control study comprising 404 UC patients and 612 controls. Moreover, 25(OH)D levels were measured by electro-chemiluminescence immunoassay in 75 UC patients and 120 controls. Our results suggested that Bsm I polymorphism frequency was significantly lower in UC patients ( P = 0.028), and the frequency of AAC haplotype formed by Bsm I, Apa I and Taq I was also significantly lower in UC patients ( P = 0.012). Moreover, Fok I polymorphism was more frequently observed in patients with mild and moderate UC as compared to those with severe UC ( P = 0.001, P < 0.001, respectively). Average 25(OH)D level was lower in UC patients than in controls (19.3 ± 6.8 vs. 21.8 ± 7.3 ng/mL, P = 0.017), and was significantly correlated with hemoglobin ( β = 0.49, P < 0.001), C-reactive protein ( β = −0.36, P < 0.001), severity of UC ( β = −0.21, P = 0.025) and Fok I polymorphism ( β = −0.20, P = 0.031) in UC patients. Interestingly, there was a significant correlation between Fok I polymorphism and vitamin D deficiency (