Geneticists from the Research Institute of the Hospital de Sant Pau – IIB Sant Pau and the IFOM – Instituto FIRC di Oncologia Molecolare of Milan (Italy), led by doctors Jordi Surrallés and Paolo Peterlongo respectively, have discovered that certain rare mutations in the FANCM gene constitute a predisposition factor for developing ER and triple-negative breast cancer, considered to be the most aggressive and with the worst prognosis among the different types of breast cancer.