Association of the TNF-α − 308G/A polymorphism with family history of type 2 diabetes mellitus in a Mexican population

► Possible association of the − 308G/A polymorphism of the TNF-α promoter gene in type 2 diabetes mellitus (DM2) patients and in non-diabetic subjects with and without family history of DM2. ► Genotyping was carried out by PCR-RFLP. ► TNF-α − 308G/A genotype frequency was significantly lower in non-diabetic subjects without DM2 relatives as compared to DM2 patients. ► Logistic regression analysis showed the association of TNF-α − 308G/A polymorphism with DM2 family history. ► TNF-α − 308G/A polymorphism is associated with DM2 family history and is a risk factor for DM2.