ORIGINAL ARTICLES   

Minerva Medica 2012 October;103(5):383-91

Copyright © 2012 EDIZIONI MINERVA MEDICA

language: English

Vitamin D receptor FokI genotype may modify the susceptibility to schizophrenia and bipolar mood disorder by regulation of dopamine D1 receptor gene expression

Ahmadi S. ¹, Mirzaei K. ¹, Hossein-Nezhad A. ², Shariati G. ³ ✉

¹ Tehran University of Medical Sciences, Tehran, Iran; ² Vitamin D, Skin and Bone Research Laboratory, Section of Endocrinology, Nutrition and Diabetes, Department of Medicine, Boston University Medical Center, Boston, USA; ³ Department of Medical Genetic, Ahvaz University of Medical Sciences, Ahvaz, Iran

AIM:This study is designed to test association of FOKI polymorphism in Vitamin D receptor (VDR) gene and its potential effect on expression of dopamine D1 receptor in schizophrenia and bipolar mood disorder as well as in healthy individuals.
METHODS: In this case-control study 196 patient with schizophrenia, 119 patients with bipolar mood disorder and 192 healthy individuals as the control group were recruited. All psychiatric disorders were diagnosed according to DSM IV criteria. Healthy control group denied any family history of such disorders. FOKI was genotyped by means of PCR-RFLP method. The mRNA was extracted from the peripheral blood mononuclear cells (PBMC) and the cDNA was synthesized.
RESULTS: Frequency of ff genotype was more common in patients with bipolar disorders compared to the healthy control group (Odds ratio=1.84, 95% CI; 0.81 to 4.17) with increased relative risk (Relative risk=1.31, CI 95%; 0.86 to 1.99). There were significant differences between relative expressions of dopamine D1 receptor gene in various genotypes. Our results indicated that the ff genotype was associated with lower expression of dopamine D1 receptor gene.
CONCLUSION: VDR as a nuclear receptor may contribute to bipolar disorders via modification of the expression of the neurotransmitters receptor such as dopamine.