GDNF rs2910702, rs3096140, and rs3812047 polymorphisms in obsessive compulsive disorder: Preliminary study

The neurobiology of obsessive-compulsive disorder (OCD) is evidenced by a strong demonstration of malfunctions in the serotonergic and dopaminergic system. Recently, glial cell line-derived neurotrophic factor (GDNF) gene polymorphisms have been emphasized in psychiatric diseases and treatment strategies that have been tried to be developed in this regard. In the literature, there are several studies investigating the relationship between GDNF gene polymorphisms and psychiatric diseases excluding OCD. Therefore, this study aimed to compare the symptomatology and GDNF gene polymorphisms in early and late-onset OCD patients. For this purpose, patients diagnosed with OCD according to DSM-V diagnostic criteria in structured clinical interviews were grouped as early and late-onset based on the age of initiation. DNA was isolated from blood samples collected from 140 subjects (70 OCD and 70 healthy controls) in EDTA tubes, and rs2910702, rs3096140, and rs3812047 polymorphisms in GDNF gene were examined by Real-Time PCR. No significant correlation was detected between GDNF and the rs2910702, rs3096140, and rs3812047 polymorphisms in early and late-onset OCD subjects (P>0.05). Failure to detect correlations between OCD and GDNF gene polymorphisms might be due to the variable expression pattern of the GDNF gene in different tissues and pathologies. Therefore, future studies might be improved by including a larger group of patients and examining a wider range of tissues for the expression pattern of GDNF.