ATM and B-cell chronic lymphocytic leukemia: Although the mutual exclusivity of ATM and TP53 alterations has already been reported, the observation that, in the series of 58 POT1 mutations reported by Puente et al. and Landau et al., only one patient also harboured a TP53 mutation is a strong argument to include POT1 alterations in the TP53 network targeted in CLL.