[(CAG)n polymorphism of the ATXN2 gene, a new marker of susceptibility for type 2 diabetes mellitus].

Objective: Estimate whether there is an association between the (CAG)n repeat in the ATXN2 gene in the Mexican population and type 2 diabetes mellitus (DM).

Methods: Epidemiological case-control study, including healthy people and diabetics. (CAG)n expansion was detected by end-point polymerase chain reaction (PCR). PCR outputs were analyzed by electrophoresis (PAGE 8%) and silver nitrate staining.

Results: (CAG)n nucleotide allele distribution in the study population was similar to that reported in central Mexico. The 22-repeat allele is the most frequent; however, there is an association with carriers of long repeats in the normal range with diabetes.

Conclusions: The results suggest that the (CAG)n repeat of the ATXN2 gene could be a causal factor for type 2 DM.