Genetic association of rs1520333 G/A polymorphism in the IL7 gene with multiple sclerosis susceptibility in Isfahan population


1 Departments of Genetics and Molecular Biology, University of Isfahan, Isfahan, Iran

2 Department of Biology, School of Sciences, University of Isfahan, Isfahan, Iran

3 Department of Immunology, Isfahan University of Medical Science, Isfahan, Iran

4 Department of Epidemiology and Biostatistics, Isfahan University of Medical Science, Isfahan, Iran


Background: Multiple sclerosis (MS) is an inflammatory neurodegenerative disease in which the insulating membrane of central nervous system is damaged. The etiology of MS includes both genetic and environmental causes. A Genome - Wide Association Study (GWAS) recognized genetic single nucleotide polymorphisms (SNP) linked with MS predisposition among which immunologically related genes are considerably over signified.
The purpose of the present study is to explore the association of rs1520333 C/T polymorphism in the IL7 gene variants with the risk of MS in a subset of Iranian population.
Materials and Methods: In this case - control study, 110 cases with MS and 110 controls were contributed. DNA was extracted from blood samples and to amplify the fragment of interest contain rs1520333 SNP, polymerase chain reaction - restriction fragment length polymorphism method was implemented for genotyping of the DNA samples with a specific restriction enzyme (MwoI).
SPSS for Windows software (version 18.0; SPSS, Chicago, IL, USA) was used for statistical analysis.
Result: We demonstrated the important association between G allele [odds ratio (OR) =1.6614, confidence interval (CI) =1.12-2.47, P = 0.0124] and GG genotype (OR = 7.45, 95% CI = 2.13-25.97, P 0.0016) of the rs1520333 SNP for susceptibility to MS after adjustment for age, and gender. OR adjusted for age, gender, and body mass index has displayed similar outcomes.
Conclusion: These results indicate that the rs1520333 SNP is a significant susceptibility gene variant for development of MS in the Iranian population. Nevertheless, functional studies are required to completely elucidate how this SNP contributed to MS pathogenesis.


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