Association of genetic variants of mannan-binding (MBL) lectin-2 gene, MBL levels and function in ulcerative colitis and Crohn’s disease

• Published in: Innate immunity (London, England) Vol. 17; no. 6; pp. 526 - 531
• Main Authors: Sivaram, G, Tiwari, Santosh K, Bardia, Avinash, Manoj, G, Santhosh, B, Saikant, R, Aejaz, Habeeb, Vishnupriya, S, Khan, Aleem A, Habibullah, CM
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.12.2011
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Colitis, Ulcerative - blood; Colitis, Ulcerative - genetics; Colitis, Ulcerative - pathology; Complement C4 - metabolism; Complement Pathway, Mannose-Binding Lectin - physiology; Crohn Disease - blood; Crohn Disease - genetics; Crohn Disease - pathology; Female; Genetic Predisposition to Disease; Genotype; Humans; India; Male; Mannose-Binding Lectin - blood; Mannose-Binding Lectin - genetics; Middle Aged; Polymorphism, Single Nucleotide; Risk Factors; Young Adult; India; genetic variants; Mannan binding lectin; ulcerative colitis; deficiency; function; Crohn’s disease
• ISSN: 1753-4259; 1753-4267; 1743-2839; 1753-4267
• DOI: 10.1177/1753425910384531

Ulcerative colitis and Crohn’s disease are the two major forms of inflammatory bowel disease (IBD). A series of reports have hypothesized interplay of genetic and environmental factors in the pathogenesis of IBD. Polymorphism in the mannan-binding lectin-2 (MBL-2) gene is known to affect the structural assembly and function thereby predisposing subjects to various diseases. The present study was designed to evaluate effect of MBL-2 gene polymorphism on MBL levels and function in IBD patients. Genomic DNA was isolated from blood samples collected from 157 ulcerative colitis, 42 Crohn’s disease and 204 control subjects. Genotyping for different polymorphic sites at exon1 of MBL-2 gene was performed by refractory mutation system-PCR and amplification followed by restriction digestion (PCR-RFLP). Serum MBL concentration and C4 deposition levels were estimated using ELISA. Mannan-binding lectin-2 genotypic variants were calculated in IBD and healthy controls. The frequency of single nucleotide polymorphisms at codon 54 was significantly higher in ulcerative colitis patients than controls (P < 0.0001). Ulcerative colitis patients with ‘codon 54’-variation showed low serum MBL concentrations coupled with altered MBL function compared to controls. In conclusion, single nucleotide polymorphism in the MBL-2 gene is an important risk factor significantly affecting MBL levels and function in the development of ulcerative colitis among Indians.