What is the molecular mechanism of cystic fibrosis and diabetes?
Cystic fibrosis is an autosomal recessive disorder, and the gene is located on chromosome 7. An individual, usually Caucasian, or Ashkenazi Jew would have to have two recessive genes for a disease phenotype to be produced. This disease affects the bodies' production of mucous, sweat and digestive juices, as produced by digestive glands and most people die in their 20's or 30's due to congestion and scarring of lungs. The CFTR gene produces a protein that attaches to the outside of the cell membrane, creating a channel for the cytoplasm inside the cell and the fluids outside the cell. Because negative chloride ions do not get transported properly, sodium ions are which positive, are attracted and combine with chlorine to form sodium chloride, or salt, inside the cell, which is then excreted in the sweat in very high concentrations. Scientists think that this also leads to thickened body secretions, including feces and mucous. These thickened secretions cause the buildup of mucous in the respiratory and digestive systems and symptoms that lead eventually to a shorter lifespan.
In diabetes, an individual with type I doesn't produce insulin and must take insulin injections. Insulin is necessary to aid the body in maintaining homeostasis, by storing excess glucose(blood sugar) as glycogen, in the liver until needed. The beta cells in the Islets of Langerhans in the pancreas are attacked by T-cells and are then lost by an autoimmune response. In type II, a person has insulin resistance possibly due to an insulin receptor on the body cells. Type I is possibly due to genetics with an environmental trigger, possibly a virus. Type II has a very strong genetic component which increases with the amount of close family members who have the disease. Obesity is an additional trigger.