A subtype of diabetes mellitus associated with a mutation of mitochondrial DNA

N Engl J Med. 1994 Apr 7;330(14):962-8. doi: 10.1056/NEJM199404073301403.


Background: Several families have been described in which a mutation of mitochondrial DNA, the substitution of guanine for adenine (A-->G) at position 3243 of leucine transfer RNA, is associated with diabetes mellitus and deafness. The prevalence, clinical features, and pathophysiology of diabetes with this mutation are largely undefined.

Methods: We studied 55 patients with insulin-dependent diabetes mellitus (IDDM) and a family history of diabetes (group 1), 85 patients with IDDM and no family history of diabetes (group 2), 100 patients with non-insulin-dependent diabetes mellitus (NIDDM) and a family history of diabetes (group 3), and 5 patients with diabetes and deafness (group 4) for the mutation. We also studied the prevalence and characteristics of diabetes in 39 patients with a syndrome consisting of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes who were known to have the mutation and 127 of their relatives (group 5).

Results: We identified 16 unrelated patients with diabetes associated with the A-->G mutation: 3 patients from group 1 (6 percent), 2 patients from group 3 (2 percent), 3 patients from group 4 (60 percent), and 8 patients from group 5 (21 percent). We also identified 16 additional subjects who had diabetes and the mutation among 42 relatives of the patients with diabetes and the mutation in groups 1, 2, 3, and 4 and 20 affected subjects among the 127 relatives of the patients in group 5. Diabetes cosegregated with the mutation in a fashion consistent with maternal transmission, was frequently (in 61 percent of cases) associated with sensory hearing loss, and was generally accompanied by impaired insulin secretion.

Conclusions: Diabetes mellitus associated with the A-->G mutation at position 3243 of mitochondrial leucine transfer RNA represents a subtype of diabetes found in both patients with IDDM and patients with NIDDM in Japan.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Base Sequence
  • Child
  • Child, Preschool
  • DNA, Mitochondrial*
  • Diabetes Mellitus, Type 1 / genetics*
  • Diabetes Mellitus, Type 1 / metabolism
  • Diabetes Mellitus, Type 2 / genetics*
  • Diabetes Mellitus, Type 2 / metabolism
  • Female
  • Humans
  • Insulin Resistance
  • Leucine / genetics
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Mutation*
  • Pedigree


  • DNA, Mitochondrial
  • Leucine