MAD1L1 and breast cancer: The recurrent regions detected in the rare CNVs in our study encompass several genes with potential functional relevance to carcinogenesis, including MAD1L1, DOT1L1, MAGEA8 and MAGEA9. MAD1L1 encodes a protein that plays an important role in maintaining spindle checkpoint functions and alterations in this gene have been associated with colon, lung, prostate and breast cancers [26,27].