The relationship between MMP-2 rs243865, MMP-9 rs398242 and CXCL-12 rs1801157 gene polymorphisms with Japanese encephalitis disease and disease outcome in North Indian population

Background & objectives: Japanese encephalitis virus (JEV) is one of the most important causes of acute and uncontrolled inflammatory disease in Asia. Matrix metalloproteinases (MMPs) and chemokines play a detrimental role in the host response to JE disease, aetiology, and disease outcome. Evidently, MMPs are widely circulated in the brain and regulate various process including microglial activation, inflammation, blood-brain barrier disruption as well as affects central nervous system (CNS). The present study was to assess the association of single nucleotide polymorphisms of MMP-2, MMP-9 and chemokine (CXCL-12/SDF1-3') in the north Indian population.

Methods: We performed case-control study comprising of 125 patients and 125 healthy controls in north Indian population. Genomic DNA was extracted from whole blood and gene polymorphism have been determined by PCR-RFLP method.

Results: MMP-2, MMP-9 and CXCL-12 gene was not significantly associated with JE disease, but homozygous (T/T) genotype of MMP-2 was statically associated with disease outcome (p=0.05, OR=0.110). A/G and G/G genotype of CXCL-12 was significantly associated with severity of disease. (p=0.032, OR=5.500, p=0.037, OR= 9.167). The serum level of MMP-2 was observed significantly increased in JE patients with homozygous (T/T) genotype whereas increased MMP-9 level was associated with heterozygous genotype.

Interpretation & conclusion: MMP-2, MMP-9 and CXCL-12 gene polymorphism were not associated with JE susceptibility, but MMP-2 may be contributed to disease protection. CXCL-12 was associated with disease severity. In our concern this is the first report from northern India.