OncoScan analysis to investigate CNV in breast tumors developed by ATM mutation carriers

The ataxia telangiectasia-mutated (ATM) gene is a moderate-risk breast cancer susceptibility gene; germline loss-of-function variants are found in up to 3% of hereditary breast and ovarian cancer (HBOC) families who undergo genetic testing. So far, no clear molecular features of breast tumors occuring in ATM deleterious variant carriers have been described, but identification of an ATM-associated tumors signature may help patients' management. To characterize hallmarks of ATM-associated tumors, absolute copy number variation and loss of heterozygosity profiles were obtained from the OncoScan SNP array. Copy number analysis of Affymetrix OncoScan HD arrays was performed on 23 formamid-fixed paraffin-embedded breast tumors. Tumors were developed by carriers of one or two mutated copies of ATM.