TABLE I

Distribution of all diabetic twins by initial zygosity and tentative diabetes classification as obtained from questionnaire survey.

No of pairs represented with diabetes
ClassificationMonozygoticDizygoticUnknown zygosityTotal
Insulin dependent diabetes mellitus24726102
Non-insulin dependent diabetes mellitus1708
Maturity onset diabetes of youth1001
Impaired glucose tolerance0101
Gestational diabetes2406
Secondary diabetes1102
Mixed type+0202
Other++2305
Unclassifiable0101
Total31916128
  • +One pair with maturity onset diabetes of youth and non-insulin dependent diabetes mellitus and one pair with gestational diabetes and non-insulin dependent diabetes mellitus.

  • ++Transient glycosuria (one case), neonatal diabetes (one), transient diabetes during childhood (one), reported to have symptoms without verified diagnosis (two cases).