In order to reveal mutations or single-nucleotide polymorphisms (SNPs) that could potentially disturb miRNA-mediated suppression of MYCN expression in neuroblastoma, the entire MYCN-3′UTR sequence from 7 MNA neuroblastoma cell lines (SMS-KCN, SMS-KCNR, SMS-KANR, SK-N-BE(2), Kelly, IMR-32 and LAN5) and 39 neuroblastoma primary tumours (34 MNA and 5 non-MNA) was sequenced. The gene discussed is MYCN; the disease is neuroblastoma.