AACR II: Six New Risk Loci for Breast Cancer Identified in Women of African Ancestry
Posted: Friday, July 17, 2020
A team of investigators identified six new risk loci that may contribute to better prediction of breast cancer risk in populations of African ancestry and perhaps provide new insights into the mechanisms of breast cancer carcinogenesis. Babatunde Adedokun, PhD, of the University of Chicago, and colleagues presented these findings during the American Association for Cancer Research (AACR) Virtual Annual Meeting II (Abstract 4613/1).
As described by the investigators, more than 180 genetic variants have been identified as risk loci for breast cancer. However, most loci were discovered using European ancestry populations. As some common susceptibility loci are shared across populations, the investigators aimed to discover new risk loci for breast cancer using a cross-ancestry genome-wide association study approach.
In total, data from five genome-wide association studies in women of African ancestry with a combined sample size of 9,241 cases and 10,192 controls were used to generate pooled breast cancer risk estimates in a fixed effect meta-analysis. Analyses were conducted separately for estrogen receptor–positive, estrogen receptor–negative, and overall breast cancer risk.
From their analysis, the investigators discovered four novel loci for overall breast cancer risk (1p13.3, 5q31.1, 15q24, and 15q26.3) and two novel loci for estrogen receptor–negative breast cancer (1q41 and 7q11.23) at the genome-wide significance level of P < 5 × 10-8. In addition, three index single nucleotide polymorphisms were found to lie within the introns of genes (KCNK2, C5orf56, and SIN3A), and the other index single nucleotide polymorphisms were located in intergenic regions (close to GSTM4 and AMPD2, CASTOR2, and the antisense DNA RP11-168G16.2).
“Replication of these loci in multiple populations and functional studies can help to identify causal variants,” the investigators proposed.
Disclosure: For full disclosures of the study authors, visit abstractsonline.com.
