Association of the Wild-Type A/A Genotype of MBL2 Codon 54 with Asthma in a North Indian Population

BACKGROUND High serum MBL level as well as polymorphisms in the mannose-binding lectin 2 (MBL2) gene resulting in MBL deficiency are involved in the mechanism of a number of non-infectious diseases such as asthma, conferring either risk or protection in different population studies. MBL being the first reactant of the MBL pathway is also a major determinant of the fate of the anaphylatoxins such as C3a and C5a, which are also pro-inflammatory mediators. The MBL2 gene polymorphisms thus control the serum levels of MBL as well as C3a and C5a. OBJECTIVE This is the first case-control study conducted in India, investigating the role of MBL2 codon 54 A/B polymorphism in asthma pathogenesis. METHODS A case-control study was performed with a total of 992 adult subjects, including 410 adult asthmatics and 582 healthy controls from regions of North India. The MBL2 codon 54 A/B polymorphism was genotyped by PCR-RFLP. RESULTS Statistical analysis for the codon 54 polymorphism revealed that the wild (A) allele was significantly associated with asthma with OR=1.9, 95% CI (1.4-2.4), and p< 0.001. CONCLUSION The MBL2 codon 54 A/B polymorphism is significantly associated with asthma and its phenotypic traits as the wild (A/A) genotype confers a significant risk towards the disease in the studied North Indian population.