The influence of genetics in diabetes mellitus type I

The relationship between genetic factors and environmental factors in diabetes is complex and still poorly understood. With regard to insulin-dependent type I diabetes, the cumulative risk for siblings of diabetic patients is 6-10% versus 0.6% in the general population. As for the effect of parental genes, the offspring of women with diabetes type I has a lower risk of disease (2.1%) than the offspring of male patients with type I diabetes (6.1%).

The reason for this discrepancy is unknown. Monozygotic twins have a 20-50%-ing concordance for type I diabetes. Susceptibility to type I diabetes is associated with the genetic expression of certain proteins encoded by the HLA major histocompatibility complex plot. These proteins are on the surface of lymphocytes and macrophages, and are believed to be important for the initiation of the autoimmune destruction of the P-cells.

Despite the fact that all known genetic markers (HLA and others) with type I diabetes, future progress in this area will produce population screening to detect genetically determined susceptibility to diabetes.
 

The influence of genetics in diabetes mellitus type II
 

Increased morbidity (non-insulin dependent) diabetes type II among family members suggests a clear genetic component in this disease. In monozygotic twins 60-90% mark-ing concordance with type II diabetes.

The cumulative risk of developing type II diabetes among siblings of diabetic parents of 10-33% versus 5% in the general population. Offspring of women with type II diabetes, say two to three times greater risk of developing diabetes than the offspring of men with the disease. The exact mode of inheritance for type II diabetes is unknown, but believed that it is polygenic.

A small percentage of patients have been established specific mutations, which encode type II diabetes. However, for most patients with specific gene has not been determined.

The relationship between environment and heredity can be found at higher levels of fasting insulin in each weight class in the offspring of two parents with diabetes type II, compared with control groups. The high content of insulin is a marker of insulin resistance, predicts progression and transition to type II diabetes.