Lack of association between leptin G2548A gene polymorphism and Behcet's disease

Background Behcet's disease is a chronic, multisystem, inflammatory disease characterized by the predominance of T-helper 1 cytokines. The disease is also characterized by infiltration of lymphocytes and neutrophils into the affected tissues. Because cytokines are involved in the regulation of lymphocyte and phagocyte functions, they may play an important role in the pathogenesis of Behcet's disease. Leptin, a member of the gp 130 family of cytokines, induces a strong T-helper 1 response and is regarded as a proinflammatory inducer. Recent studies have shown that serum leptin concentration was increased in patients with Behcet's disease and correlated with disease activity. Objectives We aimed to investigate the role of G2548A polymorphism of leptin gene in patients with Behcet's disease and compare the results with healthy controls. Patients and methods A total of 93 subjects with Behcet's disease and 125 healthy controls were included in this study. Analyses of G-2548A polymorphism of the LEP gene were performed using the PCR-restriction fragment length polymorphism technique. The genotypes (GG, GA, and AA of leptin G2548A) and alleles (G and A of leptin 2548) were scored and the frequency was estimated. The frequencies of the alleles and genotypes in patients and controls were compared. We analysed the correlation between leptin gene polymorphism and the clinical features of BD. Results Both genotype and allele frequencies were not significantly different between controls and Behcet's disease patients [OR = 0.67, 95% CI (0.35-1.29), P = 0.197 and OR = 0.77, 95% CI (0.52-1.15), P = 0.184]. We did not find any significant relationship between leptin gene polymorphism and the clinical features of BD (P > 0.05). Conclusion In the present case-control study, we found no evidence of an association between the G-2548A variant of the leptin gene and BD among Turks. Further studies are needed to investigate serum leptin level to explain the mechanisms behind the lack of association between leptin G2548A gene polymorphism and BD.