Type 1 and type 2 diabetes: what do they have in common?

Diabetes. 2005 Dec;54 Suppl 2:S40-5. doi: 10.2337/diabetes.54.suppl_2.s40.

Abstract

Type 1 and type 2 diabetes frequently co-occur in the same families, suggesting common genetic susceptibility. Such mixed family history is associated with an intermediate phenotype of diabetes: insulin resistance and cardiovascular complications in type 1 diabetic patients and lower BMI and less cardiovascular complications as well as lower C-peptide concentrations in type 2 diabetic patients. GAD antibody positivity is more common in type 2 diabetic patients from mixed families than from common type 2 diabetes families. The mixed family history is associated with more type 1-like genetic (HLA and insulin gene) and phenotypic characteristics in type 2 diabetic patients, especially in the GAD antibody-positive subgroup. Leaving out the extreme ends of diabetes phenotypes, young children progressing rapidly to total insulin deficiency and strongly insulin-resistant subjects mostly with non-Europid ethnic origin, a large proportion of diabetic patients may have both type 1 and type 2 processes contributing to their diabetic phenotype.

Publication types

  • Review

MeSH terms

  • Adult
  • Age of Onset
  • Aged
  • Diabetes Mellitus, Type 1 / classification*
  • Diabetes Mellitus, Type 1 / genetics
  • Diabetes Mellitus, Type 2 / classification*
  • Diabetes Mellitus, Type 2 / genetics
  • Genetic Predisposition to Disease
  • HLA Antigens / genetics*
  • HLA-D Antigens / genetics
  • Humans
  • Middle Aged

Substances

  • HLA Antigens
  • HLA-D Antigens