Matrixmetalloproteinase-9 gene polymorphism (rs 17576) increases the risk of depressive symptoms in bipolar disorder.

OBJECTIVES

Plasticity of neural synapses is known to be involved in the complications in bipolar disorder (BD) patients. Matrix metalloproteinases (MMPs) play a role in synaptic plasticity and memory. Even though elevated MMP-9 levels are reported in neuropsychiatric disorders, there is limited data about MMP-9 gene polymorphism in BD. The objectives of the study was to investigate genotype frequency and allele frequency of MMP-9 genetic variant (rs 17576) in BD and its association with disease severity.

MATERIALS AND

METHODS

Eighty BD cases and 80 controls were recruited in the study. MMP-9 genotyping and allele frequency and plasma MMP-9 levels were analyzed in both the groups. Hamilton depression rating scale and Young's Mania Rating Scale (YMRS) were used to evaluate severity of BD.

RESULTS

The genotype and minor allele (G allele) frequency were not significant between BD and controls. MMP-9 levels were significantly increased in BD patients with AG (P < 0.001) and GG (P = 0.022) genotypes compared to controls. BD patients with GG genotype (P = 0.038, OR: 3.26 (1.16-9.09), and G (mutant) allele (P = 0.013, OR 2.03(1.18-3.48) confer increased risk of depressive symptoms. MMP-9 was positively correlated with YMRS scale (r = 0.227, P = 0.043) in BD.

CONCLUSION

MMP-9 gene polymorphism (rs 17576) is linked with depressive symptoms in BD.