Association of the Uncoupling Protein 2-866 G/A Polymorphism with Family History and Duration of Tobacco Use Disorder in a Turkish Population.

Background: A variety of substances cause neurotoxicity by increasing intracellular oxidative stress, followed by mitochondrial dysfunction. Uncoupling proteins (UCPs) act as membrane transport proteins and reduce reactive oxygen products and mitochondrial calcium influx. We aimed to study -866 G/A gene polymorphism in tobacco use disorder (TUD) by comparing genotype distributions between TUD patients and healthy controls considering clinical parameters.

Methods: One hundred eighteen patients with TUD and 96 healthy volunteers were included in the study. The diagnosis of the patients were then confirmed, based on the DSM-5 criteria. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used to determine gene polymorphism.

Results: Our results demonstrated that the genotype distribution and allele frequencies of the TUD patient group were significantly different from those of the control group. When the genotype and the allele frequency distributions were compared between the two groups according to the family history of TUD in the patient group, the genotype and allele frequency distributions were significantly different. The GG genotype or G allele percentage was significantly higher in patients with a family history of TUD, than the patients without a family history of TUD. Comparing clinical parameters based on the genotype, the disorder's duration was significantly different between the groups of genotype. The duration of TUD was significantly shorter in patients with GG genotype than other genotypes.

Conclusions: In summary, the -866 G/A gene polymorphism might be associated with family history and duration of TUD in Turkish patients.