Abstract

BACKGROUND
Islet amyloid deposition, which is mainly composed of amylin, is a characteristic pathological finding in patients with type 2 diabetes mellitus. A missense mutation of amylin at amino acid 20, from Serine to Glycine (S20G), has been shown to be associated with type 2 diabetes in Japanese. In this study, we examined the frequency and clinical characteristics of the S20G mutation in Korean type 2 diabetic patients. METHODS: We studied 364 unrelated patients with type 2 diabetes from Seoul National University Hospital and compared them with 70 non-diabetic subjects. We measured their weight, height, blood pressure and the circumferences of their waist and hips, in order to obtain their prediabetic maximal body weight. Their Fasting plasma glucose, HbA1c, total cholesterol, triglyceride and high-density-lipoprotein (HDL) cholesterol were measured. To detect the S20G mutation, we used the polymerase chain reaction-restriction fragment length polymorphism method. The clinical features of the patients with the S20G mutation were compared with those without the mutation. RESULTS: The S20G mutation was found in 7 of the 364 diabetic patients (1.9 %) and in 1 of the 70 non-diabetic control subjects (1.4 %). The body mass index (BMI) of the patients with the S20G mutation was lower than in those with wild type (21.2+/-1.8 vs. 24.3+/-3.0 kg/m2; p<0.01). The prediabetic maximal BMI was also lower in the patients with S20G mutation (22.4+/-2.3 vs. 26.4+/-3.2 kg/m2; p<0.01) than in those with the wild type. The patients with the S20G mutation had a higher HbA1c level compared to those with the wild type (9.3+/-1.4 vs. 7.7+/-1.3%; p<0.01). CONCLUSION: The frequency of the S20G mutation of the amylin gene was 1.9% in the unrelated type 2 diabetic Korean patients. The S20G mutation is associated with a lower BMI and poor glycemic control.

• Keywords: Amylin;Mutation;Type 2 diabetes;Body mass index