Jean-Yves Masson is an internationally recognized expert in DNA repair mechanisms. His interest in DNA repair began during his PhD where he studied the function of base excision repair enzymes. He then joined the laboratory of Steve West (Cancer Research UK, Clare Hall laboratories) to study DNA double-strand break repair by homologous recombination. This process allows DNA repair but also gene replacement following CRISPR/Cas genome editing. He was recruited at the Laval University Cancer Center and became in 2013 the youngest director of the Molecular Biology, Medical Biochemistry, and Pathology Department. Dr. Masson was awarded with a FRQS Junior 1, CIHR new investigator, FRQS Junior 2, FRQS Senior and the very selective FRQS Chercheur National. He has over 100 publications in several high-impact journals such as Science and Molecular Cell, and has a patent on the use of PARP inhibitors in pulmonary hypertension. He has given talks (more than 50) in premium institutions (such as Yale and the NIH) and on several continents. Throughout his career, Dr. Masson focused on radiation and chemicals that impede DNA replication to induce DNA double-strand breaks (DSBs). Failure to remove these breaks leads genetic mutations and cancer. He is one of the few world experts on PALB2, a protein which is getting public attention as PALB2 mutations increase breast cancer by 6-8 fold. He established that PALB2 deficient cells are very sensitive to PARP inhibitors, a very promising therapeutic avenue and synthetic lethal strategies for breast/ovarian cancer.