L Ji1, L Gao, X Han. 1. Department of Endocrinology and Metabolism, People's Hospital, Peking University, Beijing 100044, China.
Abstract
OBJECTIVE: To assess the prevalence of 16189 variant (T-->C transition) of mitochondrial DNA in Chinese populations and to study the relation between mtDNA 16189 variant and insulin resistance and the role it plays in genetic predisposition to diabetes. METHODS: PCR and RELP techniques were used to examine 383 unrelated type 2 diabetics and 151 non-diabetic controls selected by random sampling. RESULTS: (1) The prevalence of 16189 variant among type 2 diabetics was significantly higher than that among the controls. (2) The prevalence of 16189 variant was significantly higher among type 2 diabetics with maternal family history than among those without maternal family history. (3) In comparison with the type 2 diabetics without 16189 variant, those with 16189 variant showed higher fasting serum insulin level, decreased insulin sensitivity index, and higher Homa insulin resistance index. (4) In the control group, no significant difference in age, gender, body mass index, waist to hip ratio, serum lipid level, fasting plasma glucose level, fasting serum insulin level, insulin sensitivity index, and Homa insulin resistance index was found between those with 16189 variant and those without 16189 variant. CONCLUSION: 16189 variant of mitochondrial DNA is one of the genetic predisposing factors for type 2 diabetes mellitus in Chinese populations. It might interfere with the energy metabolism and the production of ATP, thus causing insulin resistance in peripheral tissues.
OBJECTIVE: To assess the prevalence of 16189 variant (T-->C transition) of mitochondrial DNA in Chinese populations and to study the relation between mtDNA 16189 variant and insulin resistance and the role it plays in genetic predisposition to diabetes. METHODS: PCR and RELP techniques were used to examine 383 unrelated type 2 diabetics and 151 non-diabetic controls selected by random sampling. RESULTS: (1) The prevalence of 16189 variant among type 2 diabetics was significantly higher than that among the controls. (2) The prevalence of 16189 variant was significantly higher among type 2 diabetics with maternal family history than among those without maternal family history. (3) In comparison with the type 2 diabetics without 16189 variant, those with 16189 variant showed higher fasting serum insulin level, decreased insulin sensitivity index, and higher Homa insulin resistance index. (4) In the control group, no significant difference in age, gender, body mass index, waist to hip ratio, serum lipid level, fasting plasma glucose level, fasting serum insulin level, insulin sensitivity index, and Homa insulin resistance index was found between those with 16189 variant and those without 16189 variant. CONCLUSION: 16189 variant of mitochondrial DNA is one of the genetic predisposing factors for type 2 diabetes mellitus in Chinese populations. It might interfere with the energy metabolism and the production of ATP, thus causing insulin resistance in peripheral tissues.