A current broad definition of NB is that they represent all cells that are actively cycling, and can be labelled with fluorescent in situ hybridization (FISH) markers such as smedwi-1 (Reddien et al., 2005) and histone2B (H2B) (Guo et al., 2006; Solana et al., 2012), which act as pan-NB markers at the transcript level. The gene discussed is H2BC21; the disease is neuroblastoma.