introduction
Type 1 diabetes (T1D) (also called insulin-dependent diabetes or juvenile-onset diabetes) accounts for 5 to 10% of all diagnosed cases of diabetes. T1D is one of the most common chronic diseases in childhood and adolescence. About 1 in every 400 to 600 children and adolescents develops T1D, and more than 700,000 Americans are currently living with T1D (0.4% of the population). The number of new cases of T1D in the US has been increasing by approximately 3% per year.T1D is an autoimmune disease that can occur at any age, but it usually develops before age 30. In this type of diabetes, the islet cells of the pancreas are attacked and destroyed by the immune system. The islet cells normally produce insulin, the hormone that moves sugar from the bloodstream into the body’s cells and tissues, where it can be used for energy. When the islet cells are destroyed, little to no insulin is produced, which means that sugar cannot be moved out of the blood and blood sugar levels rise. Individuals with T1D have an increased risk of developing several serious health complications, including cardiovascular disease, kidney failure, and blindness.
The etiology of T1D is largely unknown but it has been shown that genetic factors are important risk factors. Genetic variants in 11 different genes have been identified that increase the risk of developing T1D; in the HLA-DRB1 gene on chromosome 6, the PTPN22 gene on chromosome 1, the IL-2RA gene on chromosome 10, the PTPN2 gene on chromosome 18, the ERBB3 and the C12orf30 genes on chromosome 12, the IFIH1 gene on chromosome 2, the KIAA0350 gene on chromosome 16, the INS gene on chromosome 11, the IL21 gene on chromosome 4 and the CTLA4 gene on chromosome 2.
The deCODEme Genetic Scan identifies variants in the 11 genes listed above,in customers of European descent and provides interpretation of their associated risk for the development of T1D. Currently no data are available for people of other ethnicities for the variants listed above.
risk factors
The causes for T1D are unclear, but genetic and/or environmental causes that trigger the autoimmune destruction of insulin-secreting islet cells in the pancreas seem to be the main players.- Ethnicity: People of European decent have a greater risk of developing T1D than African Americans, Asians, or Hispanics.
- Genetics: A large body of evidence indicates that genetic factors influence both the risk of developing T1D and the resistance to developing T1D. T1D tends to run in families, with an average 6% risk of two siblings developing the disease compared with a 0.4% risk of two unrelated individuals developing the disease.
more information
You can find out more information about T1D by talking with your doctor and visiting these Web sites:The American Diabetes Association
Medline Plus Medical Encyclopedia
Centers for Disease Control - Diabetics Public Resource
National Institute of Diabetes and Digestive Kidney Diseases
Juvenile Diabetes Research Foundation International