INSULIN SECRETION CAPACITY & INSULIN RESISTANCE IN SUBJECTS W/ VARIANT GENE

高亲和力的磺脲受体(SUR1)表达于胰腺的β细胞，是葡萄糖刺激的胰岛素分泌的关键成分。研究人员此前曾报道，墨西哥裔美国人的2小时血糖水平与SUR1基因附近的一个区域有关，并观察到该基因第31外显子的沉默变异，该变异与墨西哥裔美国人2型糖尿病家族中非糖尿病成员的高胰岛素浓度有关。目前尚不清楚这是由于原发性胰岛素分泌过多还是胰岛素对胰岛素抵抗的代偿性反应。这项研究将比较15名SUR1基因变异纯合子的非糖尿病墨西哥裔美国人和15名野生型等位基因纯合子的受试者的胰岛素分泌和胰岛素抵抗，这些受试者之前是圣安东尼奥糖尿病家族研究的基因分型参与者。

The high-affinity sulfonyurea receptor (SUR1) expressed on the beta cells of the pancreas is a key component in glucose-stimulated insulin secretion. The investigators have previously reported linkage of 2-hour plasma glucose levels to a region near the SUR1 gene in Mexican Americans and observed a silent variant in exon 31 of the gene which was associated with high insulin concentrations in non-diabetic members of Mexican American type 2 diabetic families. It is not known whether this is due to primary oversecretion of insulin or compensatory insulin response to insulin resistance. This study will compare insulin secretion and insulin resistance in 15 non-diabetic Mexican Americans homozygous for this variant of the SUR1 gene and 15 subjects who are homozygous for the wildtype allele and who were previously genotyped participants of the San Antonio Family Diabetes Study.