MYCN and neuroblastoma: In addition, somatic mutations in primary neuroblastomas has been reported for the transcriptional regulator ATRX (2.5% inactivating mutations), the tumor suppressor p53 (TP53; 1%–2% in primary tumors, 10% in recurrent and relapsed tumors) gene, ARID1A/1B (2%–3% inactivating mutations), PTPN11 (2.9% activating mutations), MYCN (1.7% activating mutations), NRAS (0.83% activating mutations) and BRCA2 (Cheung et al., 2012; Molenaar et al., 2012; Pugh et al., 2013; Brodeur and Bagatell, 2014).