Diabetes mellitus genetic factors

Non-alcoholic fatty liver disease begins with asymptomatic fatty liver but may progress to cirrhosis. This is a disease of exclusion elimination of any possible viral, genetic, or environmental causes must be made prior to making this diagnosis. Non-alcoholic fatty liver disease is related to numerous metabolic abnormalities. Risk factors include diabetes mellitus, dyslipidemia, obesity, and other conditions associated with increased hepatic fat.26... 

Another form of diabetes is non-insulin-dependent diabetes mellitus (NIDDM, or adult diabetes, or type II diabetes). In this case, insulin is produced and a normal insulin level is detected in blood. But for various reasons its effect is reduced. This may be caused by a reduced number of insulin receptors on cells, or reduced effectiveness in binding to these receptors. The cause is complex and may involve genetic make-up, changes in lifestyle, nutritional habits, and environmental factors. 

Akerblom, H.K., Knip, M., Hyoty, H., Rejijonen, H., Virtanen, S., Savilahti, E. and Ilonen, J. (1997). Interaction of genetic and environmental factors in the pathogenesis of insulin-dependent diabetes mellitus, Clinica Chimica Acta, 257, 143-156. 

Type 2, also known previously as non-insulin-dependent diabetes mellitus (NIDDM), accounts for 90 to 95 percent of persons with diabetes mellitus.19 This form of diabetes usually occurs in adults, especially in older individuals.35,102 Type 2 diabetes, however, can also occur in young people, and there is concern that the incidence of this disease is increasing dramatically in children and adolescents.9,83 Although the specific factors responsible for this disease are unknown, a genetic predisposition combined with poor diet, obesity, and lack of exercise all seem to contribute to the onset of type 2 diabetes.50,81,83 Increased body weight is common in patients with type 2 diabetes. 

Replacement of deficient gene products or even of organs is also utilized in the treatment of genetic disorders for example, replacement of coagulation factor VIII in hemophilia A, of or-antitrypsin in persons deficient in this factor or of pancreatic islet cells in some forms of diabetes mellitus. 

Pathogenesis and complications (A). Type I diabetes mellitus typically manifests in childhood or adolescence (juvenile onset diabetes mellitus) it is caused by the destruction of insulin-producing B cells in the pancreas. A genetic predisposition together with a precipitating factor (viral infection) could start an autoimmune reaction against B-cells. Replacement of insulin (daily dose-40U, equivalent to -1.6 mg) becomes necessary. 

Perhaps the most satisfying hypothesis for the formation of atherosclerotic lesions is that of response to injury in which lesions are precipitated by some form of injury to endothelial cells. The injury may be caused by elevated plasma levels of LDL and modified LDL (oxidized LDL), free radicals (e.g., caused by cigarette smoking), diabetes mellitus, hypertension-induced shear stress, and other factors that lead to focal desquamation of endothelial cells such as elevated plasma homocysteine levels, genetic... 

Type 2 Diabetes Mellitus This is the most prevalent form of diabetes and is characterized by both an insulin secretion defect and insulin resistance. Maturity-onset diabetes of the young (MODY), attributable to mutations of the glucose kinase gene (discussed earlier), may also be classified as type 2 diabetes mellitus. Obesity is a contributory factor and may predispose to insulin resistance with eventual development of type 2 diabetes mellitus. The precise mechanism by which obesity leads to insulin resistance in the target tissues is not understood. However, in several animal models (e.g., ob/ob mouse, db/db mouse) mutations have been identified that cause both obesity and diabetes mellitus. Unlike type 1 diabetes mellitus, type 2 is not an autoimmune disease. Studies with monozygotic twins have revealed a 90% concordance rate for type 2 diabetes mellitus, suggesting the involvement of genetic factors in the development of the disease. 

DM accounts for up to 10% of all cases of DM and is likely initiated by the exposure of a genetically susceptible individual to an environmental agent. Candidate genes and environmental factors are reportedly prevalent in the general population, but development of /3-cell autoimmunity occurs in less than 10% of the population and progresses to diabetes mellitus in less than 1% of the population. ... 

Diabetes mellitus is common in old age (Fig. 4). Genetic factors and obesity contribute to the insulin resistance which underlies the development of NIDDM (pp. 56-57). 

In addition to diabetes mellitus, Mr. Applebod has a hyperlipidemia (high blood lipid level—elevated cholesterol and triacylglycerols), another risk factor for cardiovascular disease. A genetic basis for Mr. Applebod s disorder is inferred from a positive family history of hypercholesterolemia and premature coronary artery disease in a brother. 

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