Diabetes mellitus type 2 and primarily a lack of insulin secretion. Other potentially important mechanisms associated with type 2 diabetes and insulin resistance include: increased breakdown of lipids within fat cells, resistance to and lack of incretin, high glucagon levels in the blood, increased retention of salt and water by the kidneys, and inappropriate regulation of metabolism by the central nervous system. However, not all people with insulin resistance develop diabetes, since an impairment of insulin secretion by pancreatic beta cells is also required. The World Health Organization definition of diabetes (both type 1 and type 2) is for a single raised glucose reading
Genetic causes of diabetes mellitus type 1 Genetic causes of diabetes mellitus type 1 At least 20 different chromosomal regions have been linked to type 1 diabetes (T1D) susceptibility in humans, using genome screening, candidate gene testing, and studies of human homologues of mouse susceptibility genes. The largest contribution to the pathogenesis of Type 1 Diabetes comes from a single locus called IDDM1, which comes from several genes located in the Major histocompatibility complex on the 6p21.3 chromosome. This is believed to be responsible for at least 40% of the disease's familial aggreagation. Additionally, nearly 30% of Type I Diabetes patients are heterozygous for several HLA-DQ2 (specifically