Breast Cancer Susceptibility Genes BRCA1 and BRCA2 Essay -- Breast Can

Breast cancer is the most common cancer that affects women in the United States. There are at least two majors genes (BRCA1 and BRCA2) that when they mutate can cause breast cancer. These genes can be passed from parent to child, increasing the risk of developing cancer in those child that have parent carrying these genes. BRCA1 and BRCA2 genes are located on chromosome 17 and chromosome 13 respectively. There is a 90% chance of developing breast cancer for a woman that has these mutated genes. In contrast, men carrying BRCA1 have no risk to develop breast cancer, but those carrying BRCA2 genes have high risk. It is important to note that mutations in these genes can be passed on to children by either parent. A man with a mutation is just as likely to pass this gene to his children as a woman with a mutation. Hereditary cancer occurs at young age, for instance a woman in her 20's with breast cancer is more likely to have hereditary type of cancer that a woman in her 50's. (http:www.f amilycancer.org/FamHist.stm) BRCA1 and BRCA2 are tumor suppressor genes, these genes also called "Anti- Oncogenes" which normally are involved in regulating cell growth, the proteins inhibit the proliferation of cell, which is crucial for the normal cell development and differentiation. (Britanica on line). Since the discovery of the BRCA1 and BRCA2 in 1994 and 1995 about 80% of the women who inherit mutated forms of these genes will develop breast cancer in their lifetime, usually at relatively early age and woman with BRCA1 mutations have a high risk of developing ovarian cancer as well. Kudson in 1971 proposed a two-mutation theory of cancer causation. His theory stated that all cancer are of two kind, hereditary and sporadic In the case of... .... Hereditary breast cancer. European Journal of Cancer Care. 5, 13-20 3.-Social and Ethical issues of breast cancer gene testing. Obtain from http://www.ncgr.org/gpi/odyssey/BCAN2/gtest.html 10/29/98 4.-Kinzler, Kenneth W., and Vogelstein, Bert. 1997. Breast cancer susceptibility genes BRCA1 and BRCA2. Nature. V. 386. 761-763. 5.-Marx, Jean. 1997. Possible function found for breast cancer genes. Science vol.276. 531- 532. 6.-McCain, L., and Dilligham, C., 1997. Genetics Mutation Associated with Breast Cancer . Obtain from http://www.ncgr.org/gpi/odyssey/BCAN2/genrisk.html 10/12/98 7.-Tumor suppressor gene" Obtain from http://www.eb.com:180> 10/19/98, search word: tumor suppressor gene. 8.-Breast and/or ovarian cancer risk in Jewish women: Role of the 185delAG and other mutations in the BRCA1 and BRCA2 genes. http://www.givf.com/brca1.html 10/12/98.