Breast cancer 1 gene BRCA

Without regard to therapy, potentially valuable diagnostic tests are available for presymptomatic evaluation of risk of breast cancer due to predisposition from BRCA 1 or BRCA 2 and of colon cancer related to familial adenomatous polyposis (APC gene) or hereditary nonpolyposis mismatch repair genes (MSH 2). Genetic predisposition to Alzheimer disease associated with ApoE4 is neither sufficient nor necessary to lead to the clinical condition, and no definitive therapy is available. 

Miki Y, Swensen J, Shattuck-Eidens D, et al. A strong candidate for the breast and ovarian cancer susceptibility gene BRCA 1. Science 1994 266 66-71. 

Wooster R, Neuhausen SL, Mangion J, et al. Localization of a breast cancer susceptibility gene, BRCA 2, to chromosome 13ql2-13. Science 1994 265 2088-90. 

D.L, and Vo-Dinh, T. (2006) Synthesis and characterization of SERS gene probe for BRCA-1 (breast cancer). Faraday Discussions, 132, 293-301. 

Most likely cancer gene Breast cancer (BRCA) gene Likely mechanism Inhibition of tumor-suppressor gene... 

Tnmor snppressors refer to a general class of proteins that function to slow and alter cell growth and development through a variety of mechanisms. BRCA tumor suppressor gene when mutated, increases the risk of breast cancer. 

Defects in repair by homologous recombination are associated with inheritance of one mutant allele of the BRCA-1 or BRCA-2 gene and result in predisposition to breast cancer. 

Couzin, J. The Twists and Turns in BRCA s Path. Sdmce 302, 591-593 (2003). [Genes involved in breast cancer have given researchers some big surprises and continue to do so.]... 

Levy-Lahad, E., and S. E. Plon. A Risky Business—Assessing Breast Cancer Risk. Science 302, 574-575 (2003). [A discussion of risk factors and probabilities for BRCA gene carriers.]... 

The question of who should receive screening for BRCA is unresolved. The probability of being a carrier of the gene is related to ethnicity and family history. Important factors in family history include the number of affected and unaffected family members, the age at which cancer is diagnosed, and the presence of ovarian cancer. It is currently estimated that the risk of a BRCAl mutation increases 20-fold if breast and ovarian cancer occur concurrently in one or more family members. However, as pointed out in the recent study in Ashkenazi Jewish women, the importance of family history appears to diminish as family size decreases. 

Recent studies of excision repair show that active genes (those undergoing transcription) are preferred substrates for excision repair, and within these genes the template DNA strand is preferentially repaired. Thus, the repair machinery is somehow directed toward sites where repair of DNA damage will do the most good. Transcription-coupled repair may initiate when a transcribing RNA polymerase stalls at the site of a DNA lesion. BRCA 1, a gene associated with increased risk of breast and ovarian cancer, has been implicated in transcription-coupled excision repair. 

BRCA-1 - A gene associated with an increased risk of breast and ovarian cancer that is involved in transcription-coupled excision repair. 

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