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 HLA-DQ2/DQ8) alleles. However, the HLA-DQ6 allele (HLA-DQA1*0102–DQB1*0602), if dominant, is responsible for partially preventing an organism from developing the disease. Therefore, these genetic features can be used to determine a patient's relative risk of developing the disease. Further discussion and research of the functional genomics of the pathogenesis of Type 1 Diabetes will be necessary in future studies in this field. 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.