TheG-308Avariant of the Tumor Necrosis Factor-α (TNF-α) gene is not associated with obesity, insulin resistance and body fat distribution

Tumor Necrosis Factor-α (TNF-α) has been implicated in the pathogenesis of insulin resistance and obesity. The increased expression of TNF-α in adipose tissue has been shown to induce insulin resistance, and a polymorphism at position -308 in the promoter region ofTNF-αhas been shown to increase transcription of the gene in adipocytes. Aim of this study is to investigate the role of theG-308A TNFαvariant in obesity and to study the possible influence of this mutation on body fat distribution and on measures of obesity (including Fat Free Mass, Fat Mass, basal metabolic rate), insulin resistance (measured as HOMAIR), and lipid abnormalities. TheG-308A TNFαpolymorphism has been studied in 115 patients with obesity (mean BMI 33.9 ± 0.5) and in 79 normal lean subjects (mean BMI 24.3 ± 0.3).