Frequency and Carrier Risk Associated with Common BRCA1 and BRCA2 Mutations in Ashkenazi Jewish Breast Cancer Patients

• Published in: American journal of human genetics Vol. 63; no. 1; pp. 45 - 51
• Main Authors: Fodor, Flora H., Weston, Ainsley, Bleiweiss, Ira J., McCurdy, Leslie D., Walsh, Mary M., Tartter, Paul I., Brower, Steven T., Eng, Christine M.
• Format: Journal Article
• Language: English
• Published: Chicago, IL Elsevier Inc 01.07.1998; University of Chicago Press
• Subjects: Adult; Age of Onset; Aged; Alleles; Ashkenazim; Biological and medical sciences; BRCA1; BRCA2; BRCA2 Protein; Breast cancer; Breast Neoplasms - epidemiology; Breast Neoplasms - ethnology; Carrier risk; Female; Gene Frequency - genetics; Genes, BRCA1 - genetics; Gynecology. Andrology. Obstetrics; Heterozygote; Humans; Jews; Mammary gland diseases; Medical sciences; Middle Aged; Mutation - genetics; Neoplasm Proteins - genetics; Pathology; Pedigree; Polymerase Chain Reaction; Risk; Transcription Factors - genetics; Tumors; Pathology; Carrier risk; Breast cancer; BRCA1; BRCA2; Ashkenazim; Family study; Malignant tumor; Genetic determinism; Genetic disease; Mammary gland diseases; Genetic counseling; Gene frequency; Gene; Risk factor; Genetics; Mammary gland; Mutation; Carrier; Molecular biology
• ISSN: 0002-9297; 1537-6605
• DOI: 10.1086/301903

Based on breast cancer families with multiple and/or early-onset cases, estimates of the lifetime risk of breast cancer in carriers of BRCA1 or BRCA2 mutations may be as high as 85%. The risk for individuals not selected for family history or other risk factors is uncertain. We determined the frequency of the common BRCA1 (185delAG and 5382insC) and BRCA2 (6174delT) mutations in a series of 268 anonymous Ashkenazi Jewish women with breast cancer, regardless of family history or age at onset. DNA was analyzed for the three mutations by allele-specific oligonucleotide hybridization. Eight patients (3.0%, 95% confidence interval [CI] 1.5%–5.8%) were heterozygous for the 185delAG mutation, two (0.75%, 95% CI 0.20–2.7) for the 5382insC mutation, and eight (3.0%, 95% CI 1.5–5.8) for the 6174delT mutation. The lifetime risk for breast cancer in Ashkenazi Jewish carriers of the BRCA1 185delAG or BRCA2 6174delT mutations was calculated to be 36%, approximately three times the overall risk for the general population (relative risk 2.9, 95% CI 1.5–5.8). For the 5382insC mutation, because of the low number of carriers found, further studies are necessary. The results differ markedly from previous estimates based on high-risk breast cancer families and are consistent with lower estimates derived from a recent population-based study in the Baltimore area. Thus, presymptomatic screening and counseling for these common mutations in Ashkenazi Jewish women not selected for family history of breast cancer should be reconsidered until the risk associated with these mutations is firmly established, especially since early diagnostic and preventive-treatment modalities are limited.