MYCN and neuroblastoma: The most common causative genomic alteration observed here is a MYCN gene amplification, which is present in approximately 18% of all cases, that can transcriptionally upregulate the histone-lysine N-methyltransferase enzyme Enhancer of zeste homolog 2 (EZH2, OMIM 601573), promoting an undifferentiated neuroblastoma tumor phenotype associated with poor clinical outcomes ([43], reviewed in [44]).