Early-onset type 2 diabetes: metabolic and genetic characterization in the mexican population.

The objective of this study was to investigate possible defects in the insulin sensitivity and/or the acute insulin response in a group of Mexican patients displaying early-onset type 2 diabetes and to evaluate the contribution of mutations in three of the genes linked to maturity-onset diabetes of the young. We studied 40 Mexican patients with an age of diagnosis between 20 and 40 yr in which the insulin sensitivity as well as the insulin secretory response were measured using the minimal model approach. A partial screening for possible mutations in 3 of the 5 genes linked to maturity-onset diabetes of the young was carried out by PCR-single strand conformation polymorphism analysis. A low insulin secretory capacity (AIRg = 68.5 ± 5μ U/mL·min) and a near-normal insulin sensitivity (3.43 ± 0.2 min/μU·mL × 104) were found in these patients. Among this group we found two individuals carrying missense mutations in exon 4 of the hepatocyte nuclear factor-1α (HNF-4α) gene (Asp126→His/Tyr and Arg154→Gln, respec...