291 Association of Adam33 Gene Polymorphism with Bronchial Asthma

Abstract

Background: Genetic association studies have linked occurrence of asthma with ADAM33 gene polymorphisms in different populations, but none from India. Such studies will improve individualized case management strategies over time. Objectives: Primary: To assess association of ADAM33 gene polymorphisms (F+1 G/A, S2 G/C, ST+4 A/C, ST+5 C/T, V4 C/G) with asthma. Secondary: Among asthmatics, to assess association of hospitalization, family history and severity of asthma and environmental exposure with ADAM33 gene polymorphisms. Study design: Case-control. Methods: Diagnosis of asthma was done according to GINA guidelines 2007. Controls were age and sex matched non-relatives of cases without any respiratory disease. Genotyping was done with PCR-RFLP method. Results: From August 2007 to November 2009, 211 cases (aged 74.4 months ±4.6, with 32.2% females) and 137 controls (aged 73.6 months±42.6, with 29.9% females) were recruited. Distributions of S2, ST+5 and F+1 genotypes were statistically significantly different, while allele frequencies were statistically significantly different for all 5 markers between cases and controls (p< 0.05). In ST+5 total hospitalization rate was high among cases with wild & hetero genotype [OR =3.75(95% CI: 1.33-1.63), p < 0.05]. Significant association of ST+4 wild and hetero [OR=4.147(95% CI: 1.52-11.33), p < 0.05] and ST+5 hetero [OR=2.77(.99-7.95), p < 0.05] genotypes was observed with positive family history patients. No association was found of ADAM33 gene polymorphisms genotypes in cases with severity of asthma or environmental exposure to pollutants. Conclusion: The SNPs (F+1 G/A, S2 G/C, ST+4 A/C, ST+5 C/T, V4 C/G) of the ADAM33 gene are associated with asthma.