In Poland, two founder PALB2 mutations were detected (c.509_510delGA, c.172_175delTTGT) and were associated with a 4.5-fold increased risk of breast cancer in unselected Polish women [4,21] similar to the odds ratio we found for young breast cancer patients (OR = 3.6; 95% CI 1.7–7.9). Here, PALB2 is linked to breast cancer.