In most families affected by HBOC, genetic linkage to a polymorphism on chromosome 17q21 has been found (84-86). Named BRCA1, this gene was finally cloned in 1994 (87), and one year later, BRCA2 was isolated at chromosome 13q12 (88) (Table 3). Approximately, 90% of familial ovarian cancers are caused by germline mutations in the BRCA1 gene, and most of the remaining are because of alterations in BRCA2 (89). These genes are transmitted in an autosomal dominant fashion to offspring.
Although, BRCA1 and BRCA2 appear to be important in the development of familial ovarian cancer, significantly they do not appear to affect sporadic tumors. Mutations in
Genes Involved in Familial Ovarian Cancer Syndromes
Percent of ovarian cancer cases
Percent of ovarian cancer cases in each syndrome
Hereditary breast and ovarian cancer syndrome
BRCA1 17q21 4.1
BRCA2 13p12 3.3
Hereditary nonpolyposis colorectal cancer
DNA mismatch - 2.9
Was this article helpful?
Learning About 10 Ways Fight Off Cancer Can Have Amazing Benefits For Your Life The Best Tips On How To Keep This Killer At Bay Discovering that you or a loved one has cancer can be utterly terrifying. All the same, once you comprehend the causes of cancer and learn how to reverse those causes, you or your loved one may have more than a fighting chance of beating out cancer.