Epigenetics of diabetes Type 2 Since Type 2 diabetes is characterized by chronic hyperglycaemia as a result of impaired pancreatic beta cell function and insulin resistance in peripheral tissues, it was thought that the gene might be downregulated in type 2 diabetes patients through DNA methylation. The defects in pancreatic beta cell function and insulin resistance in peripheral tissues were thought to be the result of impaired ATP production from reduced oxidative phosphorylation. It was found that the mRNA expression of PPARGC1A was markedly reduced in pancreatic islets from type 2 diabetic donors compared with that of non-diabetic donors. Using bisulfite testing, it was also
Epigenetics of diabetes Type 2 indicator of an increased risk of contracting type 2 diabetes. There are a number of genes involved in chromatin methylation. One of these genes encodes the enzyme Methylenetetrahydrofolate reductase (MTHFR). MTHFR is involved in reducing 5,10-methylenetetrahydrofolate to 5-methyltentetrahydrofolate. This reaction is a critical step in the conversion of homocysteine to methionine. The resulting product is a methyl donor that is required for CpG and histone methylation. Mutations in this gene can lead to reduced methylation at CpG sites, and these changes in methylation patterns may increase susceptibility for Type 2 Diabetes. The most common at the gene encoding MTHFR is