VNTR (CAG)n polymorphism of the ATXN2 gene and metabolic parameters of cardiovascular risk associated with the degree of obesity in the Amerindian population of Oaxaca

The ATXN2 gene has a VNTR (CAG)n with locus in exon1. Long alleles within the normal range (22–29 repeats) are associated with severe obesity in people from the United Kingdom, Indonesia and the Caribbean. To analyse the influence of VNTR (CAG)n on metabolic profile in adults with obesity and pre-obesity, as well as to estimate its effect on the risk of developing diabetes. 255 adults of Chinantec Amerindian ethnic origin were included, who underwent anthropometric and biochemical evaluation. The VNTR was amplified by end-point PCR and by 8% PAGE electrophoresis. Differences were found in the waist/hip circumference index and body mass index in the carriers of genotypes different to the one homozygous for 22 repeats with a Student's t-test value of 0.0041 and 0.0334, respectively. We also found an association with a family history of chronic disease. The VNTR of ATXN2 is associated with obesity in Mexican adults of Chinantec ancestry. El gen ATXN2 presenta un VNTR (CAG)n con locus en el exón1, los alelos largos dentro del rango normal (22–29 repeticiones) se asocian con obesidad severa en sujetos del Reino Unido, Indonesia y el Caribe. Analizar la influencia del VNTR (CAG)n del gen ATXN2 en el perfil metabólico en adultos con obesidad y pre-obesidad así como analizar su asociación con parámetros metabólicos y ambientales de riesgo cardiovascular. Se incluyeron 255 adultos de origen étnico amerindio chinanteca a quienes se les realizó evaluación antropométrica y bioquímica. El VNTR fue amplificado por PCR punto final y electroforesis PAGE al 8%. Se encontraron diferencias en la circunferencia índice cintura/cadera e índice de masa corporal en los portadores de genotipos diferentes al homocigoto de 22 repeticiones con un valor para la prueba T de Student de 0.0041 y 0.0334 respectivamente. También encontramos asociación con la historia familiar de enfermedad crónica. El VNTR de ATXN2 se asocia al grado de obesidad en adultos mexicanos con ancestria Chinanteca.