Psychiatry Investig.  2016 Sep;13(5):541-548. 10.4306/pi.2016.13.5.541.

Chemokine and Chemokine Receptor Polymorphisms in Bipolar Disorder

• Tokac D
• Tuzun E
• Gulec H
• Yılmaz V
• Bireller E
• Cakmakoglu B
• Kucukali C

• KMID: 2354475
• DOI: http://doi.org/10.4306/pi.2016.13.5.541

Abstract

OBJECTIVE
Bipolar disorder (BD) is a debilitating psychiatric disease with unknown etiology. Recent studies have shown inflammation as a potential contributing factor of BD pathogenesis. However, potential associations between chemokine and chemokine receptor polymorphisms and BD have been fundamentally understudied. To identify participation of chemokines in BD pathogenesis, we examined genetic variants of several chemokine and chemokine receptor genes.
METHODS
The study population comprised 200 patients with BD and 195 age- and sex-matched healthy controls. Genotyping of monocyte chemotactic protein 1 (MCP-1) A2518G, CCR2 V64I, CCR5 Δ32, CCR5 A55029G, stromal cell-derived factor 1 (SDF-1) 3'A, and CXCR4 C138T polymorphisms was performed using polymerase chain reaction and restriction enzyme digestion.
RESULTS
We found that CCR5-Δ32 II and CXCR4-C138T C+ genotype frequencies contributed to an increased risk for BD. However, no statistical significance could be obtained with these genotypes after Bonferroni correction. A significant asssociation was only found with MCP-1 GG and G+ genotypes, which were markedly more prevalent in patients with BD and these genotypes seemed to significantly increase the risk for BD even after Bonferroni correction.
CONCLUSION
Our findings indicate an association between genetic variants of certain chemokine and chemokine receptor (especially MCP-1) genes and BD. The exact mechanisms by which these variants contribute to BD pathogenesis and their clinical implications need to be further investigated.

Keyword

Bipolar disorder; Chemokine receptor polymorphisms; Chemokine; Pathogenesis

MeSH Terms

Bipolar Disorder*
Chemokine CCL2
Chemokine CXCL12
Chemokines
Digestion
Genotype
Humans
Inflammation
Polymerase Chain Reaction
Chemokine CCL2
Chemokine CXCL12
Chemokines