Transcriptome hierarchic clustering of the 5 syndromic cases and two sporadic control cases of MB-SHH TP53 wild-type classic variant with either homozygous PTCH1 loss (MB-SHH CTR1 or CTR; see also Additional file 1: Fig. S2) or SMO mutation (MB-SHH CTR2) showed close grouping between M6 MB-SHH/TP53-mutant and the two MB-SHH control cases, and between the two soft tissue neoplasms, desmoid fibromatosis and high-grade sarcoma, regardless of their syndromic origin (Fig. 4A). This evidence concerns the gene SMO and sarcoma.