MLPA copy number analysis of all the cases with MYCN sequence variants (as below) showed that three of the eight P44L tumours (ICH-4788, 6613 and 8819) also had evidence of MYCN gain, while single control probes on 2p (DYSF) and 2q (PAX3) detected normal copy number, indicating a focal or regional event rather than whole arm or chromosome gain. Here, PAX3 is linked to neoplasm.