Neurofibromatosis Essay, Research Paper
Neurofibromatosis is a disorder affecting the chromosomes of the human body. It is a hereditary disorder affecting the nervous system. The term neurofibromatosis actually refers to two different genetic diseases. The most common type is NF 1, and the less common type is NF 2. Both disorders are transmitted in an autosomal dominant fashion. An autosomal dominant disease is a disorder caused by the presence of a single autosomal dominant gene; an abnormal factor located on any chromosome other than the sex chromosome. They are both characterized by occurrences in multiple neurofibromas.
The main symptom of these disorders is tumors that form on the ends of nerves throughout the body. NF 1 is most commonly diagnosed during childhood. The most outstanding symptoms seem to occur during adolescence and pregnancy. Although the symptoms of NF vary and are unpredictable another common sign is brown spots on the skin. The markings on the body usually measure .5cm in diameter for younger children and can reach 1.5cm by adulthood. They can also decipher NF by observing markings or freckling on the iris.
The most common tumors occurring with NF 1 are located under the skin. They have even been found in deeper areas of the body. The amount or severity of pain from these tumors can range from minimal pain sparsely to intense pain constantly. One of the most severe results and the most apparent results of these tumors is disfigurement and orthopedic problems. These problems include scoliosis and pseudoarthrisis. There also may be some delaying in sexual maturation. There are many more learning disabilities and optic problems that may develop throughout their life.
Neurofibromatosis 2 has symptoms that usually develop much later in life compared to NF1. Most people are diagnosed with NF2 between the ages of 14 and 20. There are fewer symptoms for this type than NF1. There are fewer brown spots on the body. This disorder is noted for the frequency of tumors found on the spinal cord and brain. These tumors more often than not cause loss of hearing or a ringing sounds to occur in the ears.
The probability of being effected by neurofibromatosis is very surprising. It is actually one of the most common genetic disorders in the United States. The probability of being born with NF1 is 1 in 4000. The probability of being born with NF2 is 1 in 50000. This disorder effects all ethnic races and sexes. Because NF is an autosomal dominant genetic condition you can’t get it from other people. Statistics show that only about 50% of those affected with NF have family history of NF. The only way to get NF is from your parents. The parents can only give NF to their offspring if they are also plagued by this disorder.
In the past few years there have been huge advancements in treatment for neurofibromatosis. They still haven’t found a cure or effective treatment for this disorder. They have deciphered that NF1 effects chromosome 17 and that Nf2 effects chromosome 22. The problem with finding a cure for this disorder is that about ? of all cases occur due to new mutations of the genes. In 1990 scientists were able to clone the gene of NF1 and then produce its protein, neurofibromin. Once again in 1993 they were able to clone the gene of NF2 and create its protein, Merlin/ schwannomin. One of the only treatments for this disorder is removal of the tumors which is done like the removal of any other tumor. New advancements are made everyday toward finding the secret behind this disorder. Taking this fact into consideration, doctors must always be kept up to date concerning new procedures and treatment of this disorder.
Even though there have been huge advances in understanding this disorder there is no medical therapy available. The diagnosis of NF1 and NF2 are still largely based on clinical criteria. The diagnosis for NF1 was established by the NIH Consensus Development Conference. They stated specifically that 2 or more of the following must be present: (1) 6 or more Caf?-au-lait macules (brown spots) are present, (2) 2 or more neurofibromas (tumors), (3) freckling in the axillary or inguinal regions, (4) an optic pathway tumor, (5) 2 or more Lisch nodules, (6) a distinctive, osseous lesion, such as sphenoid wing dysplasia or thinning of the cortex of the long bones, and (7) a first-degree relative (parent, sibling, or offspring) with NF1 by the above criteria. To be diagnosed with NF2 the following must be included: (1) bilateral eight-nerve masses visualized by MR imaging or (2) a first degree relative with NF2 and either inilateral eigth-nerve masses or two of the following: neurofibroma, meninggioma, glioma, schwannoma, or jeuvanile posterior subcapsular lenticular opacity.
Neurofibromatosis used to be just another disease that only doctors knew about. One man and his life changed this forever, the Elephant Man. This disease became most well known after the broadway production of his life. The elephant man spent most of his known life as a profecional circus friek. He first appeared in1884 and his real name was Joseph Merrick. Because of his willingness to let people see him, and the play that was created around his life, the amount of reasearch done to find everything possible about this disease was certainly increased. He had numerous tumors an the right side of his body and face. His right hand was 3 to 4 times larger that the average man. His life had certainly spread the knowlage and increased the knowledge we have today of Neurofibromatosis.
Bibliography
Cook, Robert. 1994. The Gene Wars: Science, Politics, and Human Genome. W.W. Norton Co., New York.
Howell, Michael and Peter Ford. 1980. The True History of the Elephant Man. Penguin Books, New York.
Lewis, Ricki. 1994. Human Genetics, Concepts and Applications. Wm. C. Brown Publishers, Dubuque.
Lyon, Jeff. 1995. Altered Fates. W.W. Norton Co., New York
Milunsky, Aubrey MD. 1992. Heredity and Your Family’s Health. John Hopkins University Press, Baltimore.
Side, Lucy MB. 1997. “Homozygous Inactivation of the NF1 Gene in Neurofibromatosis Type 1 and Myeloid Disorders.” The New England Journal of Medicine. 336, 1713-19.