Genetic variation in the stress protein hsp70-2 gene is highly associated with obesity

• Published in: International Journal of Obesity 2001-04, Vol.25 (4), p.462-466
• Main Authors: CHOUCHANE, L, DANGUIR, J, BEJI, C, BOUASSIDA, K, CAMOIN, L, SFAR, H, GABBOUJ, S, STROSBERG, A. D
• Format: Article
• Language: English
• Subjects: Adipocytes; Adipose tissue; Biological and medical sciences; DNA polymerase; Genes; Genetic diversity; Genetic testing; Heat shock proteins; Homozygosity; Medical sciences; Metabolic diseases; Obesity; Polymorphism; Tropical medicine; Tumor necrosis factor-TNF
• ISSN: 0307-0565; 1476-5497
• DOI: 10.1038/sj.ijo.0801545

BACKGROUND:: Tumor necrosis factor-α (TNF-α) expression is increased in adipose tissue of both rodent models of obesity and obese humans. It has therefore been considered as a candidate gene for obesity. Several studies have indeed shown statistical evidence of linkage between obesity and the chromosomal region encompassing the TNF-α gene, suggesting that TNF-α and/or a nearby gene (eg hsp70 gene) is involved in the onset and progression of weight gain. We designed a case-controlled study to investigate the potential association of polymorphism of the TNF-α and that of a stress protein (hsp70-2) with obesity. METHODS:: We used the polymerase chain reaction and restriction enzyme digestion to characterize the variation of the TNF-α promoter region and that of the hsp70-2 gene in 343 unrelated Tunisian patients with obesity and 174 healthy control subjects. RESULTS:: Analysis of the -308 TNF-α polymorphism in patients with obesity and in control subjects did not reveal an association between TNF-α alleles and obesity.In contrast, polymorphism analysis of the hsp70-2 gene in patients with obesity demonstrated highly significant differences in genotypic distribution of this bi-allelic locus compared to the control subject group. Homozygosity for one hsp70-2 allele was highly associated with obesity (r2 =7.12; P