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Purpose: Studies suggest that African American women are less likely to pursue BRCA1/2 genetic testing than white women. However, such studies are often confounded by unequal access to care., Methods: Data from 132 African American and 636 white women, obtained from a clinical database at the University of North Carolina (Chapel Hill, NC) between 1998 and 2005, were analyzed to assess BRCA1/2 genetic testing uptake. Importantly, the clinical setting minimized barriers of both cost and access. Race and time of new breast cancer diagnosis (recent v > 1 year before genetic evaluation) were assessed for association with BRCA1/2 testing uptake using multivariable logistic regression models., Results: Both race (P = .0082) and a recent diagnosis of breast cancer (P = .014) were independently associated with testing uptake. African American women had a lower estimated odds of pursuing testing than white women (odds ratio [OR], 0.54; 95%CI, 0.34 to 0.85), and women with a recent diagnosis had a higher OR than those with a remote diagnosis (OR, 1.58; 95% CI, 1.10 to 2.29). In a race-stratified analysis, there was no statistical evidence for association between recent status and testing uptake in the larger white stratum (OR, 1.38, P = .13) while there was for the smaller African American sample (OR, 2.77, P = .018). The test of interaction between race and remote status was not significant (P = .15)., Conclusion: African American race was associated with an overall decreased uptake of BRCA1/2 genetic testing, even when barriers of ascertainment and cost were minimized. However, among African American women, a recent diagnosis of breast cancer was associated with substantially increased uptake of testing.

While many individual risk factors have been defined for breast cancer, a family history was recognized long ago as one of the most potent. Mutations within BRCA1 or BRCA2, both identified about 10 years ago, are responsible for the majority of inherited breast cancer. By virtue of her age alone, a young woman diagnosed with breast cancer has a greatly elevated probability to carry a BRCA mutation. Other risk factors, including a personal or family history of ovarian cancer, bilateral breast cancer or Jewish ancestry, only serve to increase that chance. It is critical that clinicians caring for a young woman understand their patient's elevated risk to carry such a mutation and thoughtfully investigate this risk. Upon identification of a mutation in a young woman there are many consequences which necessitate careful consideration of various treatment and preventative options including prophylactic mastectomy and oophorectomy. Finally, the diagnosis of breast cancer in a young woman and the attendant genetic implications have immediate and serious consequences for her family members. Genetic professionals can help navigate the complex technical and psychosocial issues. This chapter explores the molecular, clinical and ethical intricacies of BRCA genetic testing.

The identification of genomic rearrangements involving more than 0.5 kb of the BRCA1 gene has confirmed a more complex mutation spectrum than was initially appreciated. Genomic rearrangements in BRCA1 represent 15% of all mutations in a group of French and American breast and ovarian cancer families and 36% of all mutations in a group of Dutch families. The rearrangements described to date range in size from 510 bp to 23.8 kb, are found throughout the gene, and are most frequently attributable to homologous recombination. We describe the identification of rearrangements in two breast and ovarian cancer families that involve 3.4 and 11.5 kb of the BRCA1 gene and span multiple exons but maintain the reading frame. Both gene rearrangements appear to result from Alu-mediated homologous recombination and have been detected by using a combination of protein truncation analysis and Southern blot analysis. These rearrangements result in the loss of amino acids that lie at the carboxy-terminus of the protein and that have previously been shown to have functional significance. Because these rearrangements result in the deletion of exons but maintain the reading frame, they may provide insights into specific regions and amino acids that have functional significance for the BRCA1 protein.

Constitutive large deletions and duplications of BRCA1 resulting from Alu-mediated recombination account for a significant proportion of disease-causing mutations in breast and/or ovarian cancer families. Using Southern blot analysis and a protein truncation test (PTT), we have identified a 7.1 kb germline deletion in two families with breast and ovarian cancer. This deletion, which includes exons 8 and 9 and leads to a frameshift at the mRNA level, appears to result from homologous recombination between closely related Alu repeats, one in intron 7 and one in intron 9. In addition to the transcript without exons 8 and 9, analysis of RNA by protein truncation test from individuals with the deletion also identified the presence of alternative splicing of exon 10 from the mutant allele, which results in a transcript that lacks exons 8, 9, and 10. Of interest is that the two American families who carry this deletion are of northern European ancestry and share a common haplotype, suggesting that this deletion may represent a founder mutation. Genes Chromosomes Cancer 28:300-307, 2000., (Copyright 2000 Wiley-Liss, Inc.)