[Mutations in the mitochondrial gene in patients with NIDDM]
1Internal Medicine III, Faculty of Medicine, University of Tokyo.
Nihon Rinsho. Japanese Journal of Clinical Medicine
|October 1, 1994
Summary
A specific mitochondrial mutation (3243 bp) is linked to diabetes in Japanese families. This condition, often maternally inherited, presents with hearing loss and insulin deficiency, suggesting a distinct diabetes subtype.
Area of Science:
- Genetics
- Endocrinology
- Mitochondrial Diseases
Background:
- The A to G mutation at position 3243 in mitochondrial leucine tRNA (3243 bp mutation) has been identified in families with diabetes and deafness.
- Understanding the prevalence and clinical characteristics of diabetes associated with this mutation is crucial.
Purpose of the Study:
- To investigate the prevalence and clinical features of diabetes mellitus associated with the 3243 bp mitochondrial DNA mutation in the Japanese population.
- To determine if this mutation represents a distinct subtype of diabetes.
Main Methods:
- Analysis of diabetes cosegregation with the 3243 bp mutation in over 30 Japanese families.
- Prevalence study of the 3243 bp mutation in randomly selected diabetic patients and non-diabetic controls.
Main Results:
- Diabetes was found to cosegregate with the 3243 bp mutation in more than 30 Japanese families.
- The prevalence of the 3243 bp mutation was 0.9% in diabetic patients versus 0% in controls.
- Diabetes associated with the 3243 bp mutation often shows maternal inheritance, hearing disturbance, insulin deficiency, and a tendency towards progression.
Conclusions:
- The 3243 bp mitochondrial mutation is significantly more prevalent in diabetic patients than in controls in Japan.
- Diabetes mellitus associated with the 3243 bp mutation exhibits distinct clinical features, supporting its classification as a new subtype of diabetes mellitus.
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