Genetic+Disorders+DF

AUTOSOMAL RECESSIVE DISORDERS

 * Tay-sachs KAT
 * Autosomal Recessive Disorder
 * This is due to a mutation in a gene for HexA. This gene codes for an enzyme Hex A that breaks down lipids in neurons in the brain. When the lipids build up if you have a mutation in both copies of the gene, this kills brain cells. A child looses mental skills and usually becomes completely paralyzed by age 5.
 * Cystic Fibrosis MASSEY
 * Autosomal Recessive Disorder
 * This is caused by a mutation in a gene for a cell membrane protein in the lungs that normally pumps chloride ions into and out of the cells. When both copies of the gene are mutated, chloride cannot be pumped properly and mucus builds up in the lungs. The lungs will eventually fail and a lung transplant may be the only way to save the person's life. This disorder is most common in caucasians. (1 in 3300 are carriers while only 1 in 15000 African Americans are carriers)
 * PKU DEDE
 * Autosomal Recessive Disorder
 * The enzyme made by the gene mutated in this disorder normally breaks down phenylalanine. If a person inherits two mutated copies of this gene, phenylalanine builds up in the brain and this causes mental retardation. Phenylalanine is an amino acid found in protein, so a diet very low in protein is one treatment. Also, phenylalanine is found in nutrasweet. So people with PKU cannot drink most diet drinks.
 * Sickle Cell Disease RJ
 * Autosomal Recessive Disorder
 * This is due to mutations in the genes for hemoglobin protein. If you inherit two copies of the mutated gene, all of the hemoglobin proteins have the wrong shape and this causes the red blood cells to have an abnormal shape. Instead of round, the red blood cells have a sickle shape. The sickle cells can get caught in joints causing severe pain and can damage organs. There is no cure, but blood transfusions can help.
 * Beta Thalassemia CHANDLER
 * Autosomal Recessive Disorder
 * Like Sickle Cell, this is due to a mutation in the gene for hemoglobin. If you inherit two bad copies of this gene, no hemoglobin is made and red blood cells die. If you have fewer red blood cells, this is called anemia. Severe anemia like this can cause death.
 * Hemochromatosis KEATON
 * Autosomal Recessive Disorder
 * This disorder is caused when a person has inherited mutations in both of the genes for a protein called HFE that is normally on the cell membrane. When a person has no normal HFE, then iron levels build up in the blood. This can cause liver damage and liver cancer. Donating blood can help reduce the iron levels in the blood.

AUTOSOMAL DOMINANT DISORDERS

 * Mafan Syndrome HARRISON
 * Autosomal Dominant Disorder
 * Caused by a mutation in the fibrillin gene. The fibrillin protein is found in connective tissue (basically the 'filler' cells that connect and fill out your body). Tendons and ligaments are examples of connective tissue. With just one bad copy of the fibrillin gene, tendons and ligaments are weakened. People with the disorder often have long limbs because of this weakening of tendons and ligaments, but more dangerously this can weaken the heart and cause the spine to curve. Abraham Lincoln may have had Marfan's syndrome.
 * Huntington Disease BLAIR
 * Autosomal Dominant Disorder
 * The huntintin gene is mutated in this disorder. Normally this gene makes a protein important to brain cells. With just one mutated copy, the protein that is produced is abnormal and causes the brain cells to die starting in middle age. Brain functions decline until death. There is no cure.
 * Neurofibromatosis FAITH
 * Autosomal Dominant Disorder
 * In this disorder, proteins responsible for controlling neuron cell growth are mutated. With just one mutated copy, the neurons can grow uncontrollably causing tumors in the nerves. These tumors can damage the nerves and also the skin covering the nerves. There is no cure.

X-LINKED RECESSIVE DISORDERS

 * Muscular dystrophy EMILY
 * X-linked recessive disorder
 * Occurs when there is mutation in the gene for the dystrophin protein. This is an important muscle protein. If a person has no good copies of the dystrophin gene muscle cells will die. A person with this disorder will have difficulty walking and talking. There is no cure, but physical therapy and some drugs can slow the progress of muscle cell death.
 * Hemophilia BILL
 * X-linked recessive disorder
 * Occurs when there is a mutation in a clotting factor gene. The gene is found on the X-chromosome. If both copies of the gene are mutated, the blood does not clot well and a person can easily bleed to death. For treatment, patients get injections of purified clotting factor proteins.
 * Fragile X PATRICIA
 * X-linked recessive disorder
 * Caused by a mutation in the FMR1 gene on the X chromosome. The protein coded for by this gene is required for brain development. When there is a mutation in the FMR1 gene, mental retardation results.

AUTOSOMAL RECESSIVE OR AUTOSOMAL DOMINANT DISORDER

 * Polycystic Kidney Disease CAROLINE
 * autosomal dominant: only one mutated gene required
 * autosomal recessive: two copies of the mutated gene required
 * In either case, kidney cells do not develop into kidney structures but instead into cysts. The genes involved code for proteins that signal that the cells are kidney cells. When that signaling system breaks down the cells do not develop into kidney cells but just into cysts. The kidneys will eventually fail and a kidney transplant may save the person's life.