Similarly, the risk of diabetes appears to be elevated in the children of older parents, and functions related to glucose and carbohydrate metabolism are enriched among the genes whose methylation is correlated with maternal age, including such candidate genes for obesity and diabetes as IRS1, IRS2, DUSP12, DYRK2, and ARNT. Here, ARNT is linked to obesity due to melanocortin 4 receptor deficiency.