Skip NavigationSkip to Content

Next Generation Sequencing Reveals High Prevalence of BRCA1 and BRCA2 Variants of Unknown Significance in Early-Onset Breast Cancer in African American Women.

  1. Author:
    Ricks-Santi, Luisel
    McDonald, J Tyson
    Gold, Bert
    Dean, Michael
    Thompson, Nicole
    Abbas, Muneer
    Wilson, Bradford
    Kanaan, Yasmine
    Naab, Tammey J
    Dunston, Georgia
  2. Author Address

    Cancer Research Center, Hampton University, Hampton, Virginia., Laboratory of Experimental Immunology, National Cancer Institute, Frederick, Maryland., Howard University Cancer Center, Washington, DC., National Human Genome Center, Howard University Department of Community and Family Medicine, Washington, DC., Department of Microbiology, Howard University School of Medicine, Washington, DC.,
    1. Year: 2017
    2. Date: Apr 20
  1. Journal: Ethnicity & disease
    1. 27
    2. 2
    3. Pages: 169-178
  2. Type of Article: Article
  3. Article Number: 169-178
  1. Abstract:

    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. 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. 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). 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.

    See More

External Sources

  1. DOI: 10.18865/ed.27.2.169
  2. PMID: 28439188
  3. PMCID: PMC5398176

Library Notes

  1. Fiscal Year: FY2016-2017
NCI at Frederick

You are leaving a government website.

This external link provides additional information that is consistent with the intended purpose of this site. The government cannot attest to the accuracy of a non-federal site.

Linking to a non-federal site does not constitute an endorsement by this institution or any of its employees of the sponsors or the information and products presented on the site. You will be subject to the destination site's privacy policy when you follow the link.

ContinueCancel