A single gene disorder is an inherited disease caused by a gene mutation. When a gene mutates, or changes, the gene may not function as it should, or it may stop functioning entirely. The result is a disease process affecting the embryo. If you or your partner may pass on an inherited disorder, in vitro fertilization combined with preimplantation genetic diagnosis (PGD) can help minimize the risk.
There are several single gene disorders that can be tested for.
- Hemophilia is a disorder that causes the blood to clot much more slowly than normal, resulting in substantial bleeding from very minor injuries. Hemophilia is linked to a recessive gene on the X-chromosome and almost exclusively affects men and boys.
- Cystic Fibrosis is a chronic disease of the lungs and digestive system. A defective gene and its protein product produce thick, sticky mucus that obstruct the lungs and cause serious lung infections. Cystic fibrosis also obstructs the pancreas and disrupts the normal process of digesting food.
- Tay-Sachs disease is a disorder that progressively destroys nerve cells in the brain and spinal cord. The disorder is very rare in the general population and more common in people of Ashkenazi (eastern and central European) Jewish heritage.