1. Finding the Ancestral Link among Women with Triple-Negative Breast Cancer
Nuria Astrid Perez Varela
Mentor: Leticia Márquez-Magaña, PhD
Description:
The ancestral nature of the maternal linage of 100 latinas was identified to determine if an
ancestral link exists among patients diagnosed with this form of cancer.
Abstract
Triple negative breast cancers (TNBC) are characterized by the absence of estrogen
receptor, progesterone receptor, and HER-2 expression making them especially deadly.
This is because these receptors are the targets for highly successful treatments for breast
cancer, and their absence makes it difficult to treat TNBC. TNBC is found in 15% of U.S.
women with breast cancer, African-American women having the highest incidence
(Carey 2006) . In sub-Saharan Africa the rate of TNBC appears to be much higher. A
recent study of 75 breast cancer patients in Ghana found that 82% had TNBC (Stark
2010). The high rates of TNBC in African American and Ghanaian women suggest it may
have a genetic ancestral component. We studied the mtDNA type of 100 Latinas with and
without TNBC to determine if an ancestral link exists among patients diagnosed with this
form of cancer. Latinas are a heterogeneous human sub-population having European,
Native American, and African ancestry. The ancestral nature of their maternal lineage can
be determined by mtDNA typing. Therefore the mtDNA type of 31 latinas with TNBC,
34 with triple positive breast cancer, and 35 unaffected controls will be determined.
Preliminary results show that a TNBC cell line has a mtDNA type indicative of African
ancestry; whereas, a triple-positive cell line has a mtDNA type indicative of European
ancestry. Consequently, we predict that TNBC samples will display greater percentage of
African ancestry. The identification of an ancestral link among women with TNBC may
allow for development of methods for its early detection and treatment.
Work cited
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