what happens in the disorder ALKAPTONURIA, CYSTIC FIBROSIS and HUNTINGTON'S DISEASE?what are their symptoms and what does they results to?

Alkaptonurea- It is an  inherited autosomal recessive genetic disorder in which there is a defect in the enzyme that codes for degradation of tyrosine.  As a result of this disorder an compound commonly known as alkapton (homogentisic acid) accumulates in the blood and is massively excreted in urine.  It can lead to damage of heart valves, cartilages etc.

Cystic fibrosis- It is an autosomal recessive disorder. It caused due to a mutation in a gene on chromosome 7. The gene codes for chloride channel which allows diffusion of chloride ions into and out of epithelial cells and is located in the cell surface membranes of these cells. In the sufferers of this disease, this chloride channel does not function.

One of the normal function of the epithelial cells is to form mucus glands which secrete mucus. In cystic fibrosis patients this mucus becomes abnormally thick and sticky because the normal outward flow of chloride ions is prevented. The parts of the body that is most affected are the lungs pancreas and liver. In the pancreas, fibrous patches called cysts develop which give the disease its name. The thick mucus clogs up the airway of lungs, and the branches of the pancreatic duct and the bile duct from the liver into the gut. Repeated lung infections are caused, frequent digestive problems, including poor release of pancreatic enzymes and poor absorption of digested food. Males and females are mostly infertile because of this disease.

Hungtington's disease- It is also known as Hungtington's chorea and it is caused by an autosomal mutation which is dominant. This disease causes progressive deterioration of brain cells and gradual loss of motor control resulting in uncontrollable shaking and dance like movements (chorea). Intellectual ability is lost, hallucinations , mood changes, personality changes, memory loss may all occur.