Evaluation of leptin and leptin receptor gene polymorphisms in bipolar disorder: focus on depressive episodes with...

Objective: Our study aims to examine the effect of leptin (LEP) (-2548 G > A) (rs7799039) and leptin receptor (LEPR) (668 A > G) (rs1137101) gene polymorphisms on the etiopathogenesis of bipolar disorder (BD) by comparing them with a control group, as well as their association with depressive episodes featuring atypical symptoms.

Methods: The study included a sample of 103 individuals with BD and 103 healthy volunteers. Gene polymorphisms were identified from DNA samples through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: The distribution of LEPR genotypes was significantly different between BD patients and healthy controls. Specifically, the homozygous LEPR GG genotype was more common in the control group than in BD patients. Additionally, genotype frequency distributions among BD patients varied significantly based on the presence of atypical depressive episodes. The LEPR AA and LEP GG genotypes were significantly more common among patients with a history of atypical depression. Logistic regression showed that the LEP polymorphism and Hamilton Depression Rating Scale (HAM-D) score predict atypical depression in BD.

Conclusion: In summary, while the LEPR polymorphism is linked to BD, the LEP polymorphism and symptom severity appear to predict atypical depressive episodes.