NFIB and in situ carcinoma: To investigate the relationship between CIS genes and regions of chromosomal lossor gain defined within primary tumours [35,36], a GISTIC analysis was also performed [37]: PTEN maps within a well-established region of commonchromosomal loss on 10q associated with SHH tumours [38], and both NFIB and TMEM45B were found to be presentwithin peak regions of localised copy number gain (Additional file 4: Figure S2).