Objectives: The study aimed to investigate the association of Crohn's disease (CD) with transcobalamin II (TCN2) polymorphisms and serum homocysteine, folate, and vitamin B12 levels. Methods:TCN2 (rs1801198, rs9606756) were genotyped by iMLDR in 389 CD patients and 746 controls. Furthermore, 102 CD patients and 153 controls were randomly selected for examination of serum homocysteine, folate, and vitamin B12 levels by enzymatic cycling assay and chemiluminescence immunoassay, respectively. Results: Mutant allele (G) and genotype (AG + GG) of (rs9606756) were higher in CD patients than in controls (both p < 0.05). So were they in ileocolonic CD patients and stricturing CD patients compared to controls (all p < 0.05). Mutant allele (G) and genotype (CG + GG) of (rs1801198) were more prevalent in stricturing CD patients than in controls (both p < 0.05). Compared to controls, average homocysteine level was enhanced in CD patients (p = 0.003), whereas average folate and vitamin B12 levels were reduced in CD patients (both p < 0.001). The prevalence of hyperhomocysteinemia, folate deficiency, and vitamin B12 deficiency was higher in CD patients than in controls (all p < 0.01). Both folate deficiency and vitamin B12 deficiency were independently related to risk of CD (both p < 0.01). Conclusion:TCN2 (rs1801198, rs9606756) polymorphisms as well as folate deficiency and vitamin B12 deficiency are correlated with CD.
P148 Screening with holotranscobalamin is superior to serum B12 in identifying vitamin B12 deficiency in patients with Crohn's disease
