Type 1 diabetes is a polygenic disease, meaning many different genes contribute to its expression. Depending on locus or combination of loci, it can be dominant, recessive, or somewhere in between. The strongest gene, IDDM1, is located in the MHC Class II region on chromosome 6, at staining region 6p21. This is believed to be responsible for the histocompatibility disorder characteristic of type 1: Insulin-producing pancreas cells (beta cells) display improper antigens to T cells. This eventually leads to the production of antibodies that attack these beta cells. Weaker genes are also located on chromosomes 11 and 18.
Environmental factors can strongly influence expression of type 1. A study showed that for identical twins, when one twin had type 1 diabetes, the other twin only had type 1 30%–50% of the time. Despite having the exact same genome, one twin had the disease, where the other did not; this shows that environmental factors, in addition to genetic factors, can influence disease prevalence.
This article is licensed under the Creative Commons Attribution-ShareAlike License.
It uses material from the Wikipedia article on
"Diabetes mellitus type 1"
All material adapted used from Wikipedia is available under the terms of the
Creative Commons Attribution-ShareAlike License.
Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.
Last Updated: Feb 1, 2011