The frequency and kind of ATM rare variants detected in NB specimens was similar to that found in a series of 60 healthy controls (data not shown), but 14/50 of the tumor samples or 6/16 of the cell lines considered (NB16, NBL-S, NGP, SK-N-AS, SK-N-DZ, LAN-6) were found to have a complete hemizygous ATM deletion as assessed by multiplex ligation-dependent probe amplification assay (MLPA). This evidence concerns the gene ATM and neuroblastoma.