Marc J Williams, Michael Uj Oliphant, Vinci Au, Cathy Liu, Caroline Baril, Ciara O'Flanagan, Daniel Lai, Sean Beatty, Michael Van Vliet, Jacky Ch Yiu, Lauren O'Connor, Walter L Goh, Alicia Pollaci, Adam C Weiner, Diljot Grewal, Andrew McPherson, McKenna Moore, Vikas Prabhakar, Shailesh Agarwal, Judy E Garber, Deborah Dillon, Sohrab P Shah, Joan Brugge, Samuel Aparicio
Cancer-associated mutations have been documented in normal tissues, but the prevalence and nature of somatic copy number alterations and their role in tumor initiation and evolution is not well understood. Here, using single cell DNA sequencing, we describe the landscape of CNAs in >42,000 breast epithelial cells from women with normal or high risk of developing breast cancer. Accumulation of individual cells with one or two of a specific subset of CNAs (e.g. 1q gain and 16q, 22q, 7q, and 10q loss) is detectable in almost all breast tissues and, in those from BRCA1 or BRCA2 mutations carriers, occurs prior to loss of heterozygosity (LOH) of the wildtype alleles...
May 3, 2024: bioRxiv