Germline mutation rate in African-American women in Arkansas with a personal and/or family history of breast cancer

Background: Variants of unknown significance (VUSs) have been identified in BRCA1 and BRCA2 and account for the majority of all identified sequence alterations. Notably, VUSs occur disproportionately in people of African descent hampering breast cancer (BCa) management and prevention efforts in the population. Our study sought to identify and characterize mutations associated with increased risk of BCa at young age.Methods: In our study, the spectrum of mutations in BRCA1 and BRCA2 was enumerated in a cohort of 31 African American women of early age at onset breast cancer, with a family history of breast or cancer in general and/or with triple negative breast cancer. To improve the characterization of the BRCA1 and BRCA2 variants, bioinformatics tools were utilized to predict the potential function of each of the variants.Results: Using next generation sequencing methods and in silico analysis of variants, a total of 197 BRCA1 and 266 BRCA2 variants comprising 77 unique variants were identified in 31 patients. Of the 77 unique variants, one (1.3%) was a pathogenic frameshift mutation (rs80359304; BRCA2 Met591Ile), 13 (16.9%) were possibly pathogenic, 34 (44.2%) were benign, and 29 (37.7%) were VUSs. Genetic epidemiological approaches were used to determine the association with variant, haplotype, and phenotypes, such as age at diagnosis, family history of cancer and family history of breast cancer. There were 5 BRCA1 SNPs associated with age at diagnosis; rs1799966 (P=.045; Log Additive model), rs16942 (P=.033; Log Additive model), rs1799949 (P=.058; Log Additive model), rs373413425 (P=.040 and .023; Dominant and Log Additive models, respectively) and rs3765640 (P=.033 Log Additive model). Additionally, a haplotype composed of all 5 SNPs was found to be significantly associated with younger age at diagnosis using linear regression modeling (P=.023). Specifically, the haplotype containing all the variant alleles was associated with older age at diagnosis (OR= 5.03 95% CI=.91-9.14).Conclusions: Knowing a patient’s BRCA mutation status is important for prevention and treatment decision-making. Improving the characterization of mutations will lead to better management, treatment, and BCa prevention efforts in African Americans who are disproportionately affected with aggressive BCa and may inform future precision medicine genomic-based clinical studies. Ethn Dis. 2017;27(1):169-178; doi:10.18865/ed.27.2.169

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Recruiting African American Women to Participate in Hereditary Breast Cancer Research

Journal of Clinical Oncology ◽

10.1200/jco.2004.00.4952 ◽

2005 ◽

Vol 23 (31) ◽

pp. 7967-7973 ◽

Cited By ~ 36

Author(s):

Chanita Hughes Halbert ◽

Kiyona Brewster ◽

Aliya Collier ◽

ChaChira Smith ◽

Lisa Kessler ◽

...

Keyword(s):

Breast Cancer ◽

African American ◽

Genetic Counseling ◽

African American Women ◽

Medical Practices ◽

American Women ◽

Study Enrollment ◽

Community Oncology ◽

History Of ◽

History Of Cancer

Purpose This study evaluated the process of recruiting African American women to participate in genetic counseling research for BRCA1 and BRCA2 (BRCA1/2) mutations with respect to referral, study enrollment, and participation in genetic counseling. Patients and Methods African American women (n = 783) were referred for study enrollment. Results Of 783 referrals, 164 (21%) women were eligible for enrollment. Eligible women were most likely to be referred from oncology clinics (44%) and were least likely to be referred from general medical practices (11%; χ2 = 96.80; P = .0001). Overall, 62% of eligible women enrolled onto the study and 50% of enrollees completed genetic counseling. Women with a stronger family history of cancer (odds ratio [OR] = 3.18; 95% CI, 1.36 to 7.44; P = .01) and those referred from oncology clinics and community oncology resources (OR = 2.97; 95% CI, 1.34 to 6.58; P = .01) were most likely to enroll onto the study. Referral from oncology clinics was associated significantly with participation in genetic counseling (OR = 5.46; 95% CI, 1.44 to 20.60; P = .01). Conclusion Despite receiving a large number of referrals, only a small subset of women were eligible for enrollment. Oncology settings were the most effective at identifying eligible African American women and general medical practices were the least effective. Factors associated with enrollment included having a stronger family history of cancer and being referred from oncology clinics and community oncology resources. Referral from oncology clinics was the only factor associated significantly with participation in genetic counseling. Education about hereditary breast cancer may be needed among primary care providers to enhance appropriate referral of African American women to genetic counseling for BRCA1/2 mutations.

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Breast Cancer Risk Estimates for Relatives of White and African American Women With Breast Cancer in the Women's Contraceptive and Reproductive Experiences Study

Journal of Clinical Oncology ◽

10.1200/jco.2005.04.1087 ◽

2006 ◽

Vol 24 (16) ◽

pp. 2498-2504 ◽

Cited By ~ 16

Author(s):

Michael S. Simon ◽

Jeannette F. Korczak ◽

Cecilia L. Yee ◽

Kathleen E. Malone ◽

Giske Ursin ◽

...

Keyword(s):

Breast Cancer ◽

African American ◽

Family History ◽

Breast Cancer Risk ◽

Cancer Risk ◽

African American Women ◽

White Women ◽

Cancer Risks ◽

Risk Estimates ◽

History Of

Purpose Family history is a well-recognized risk factor for breast cancer. Familial aggregation and segregation analyses have estimated breast cancer risk based on family history primarily for white women; such information is limited for African American (AA) women. The purpose of this report is to update breast cancer risk estimates associated with a family history of breast cancer for white and AA women. Methods We used family cancer history from 2,676 white and 1,525 AA women with breast cancer (probands) in the population-based National Institute of Child Health and Human Development's Women's Contraceptive and Reproductive Experiences (CARE) Study to estimate age-specific breast cancer risks in their first degree adult female relatives. Cumulative hazard curves were calculated for relatives of all probands using Cox proportional hazards models, and were stratified by the proband's race and age at diagnosis and number of relatives affected. Results Breast cancer risks for white and AA women with a family history of the disease are similar through age 49 years, but diverge afterwards, with higher risks by age 79 in white women than in AA women (17.5% [SE, 0.9%] v 12.2% [SE, 1.1%]; P < .001). These risks increase as the number of affected first degree relatives increases, reaching 25.2% (SE, 3.4%) and 16.9% (SE, 4.0%) in white and AA women with more than one affected relative, respectively (P = .3). Conclusion We found age-related racial differences in breast cancer risk in women with a family history of breast cancer and have updated risk estimates for white and AA women for clinical use.

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