PRX and neurofibromatosis: It was unexpected to find that the transcripts for the myelin protein periaxin (PRX), the genes associated with neurofibromatosis (NF1, NF2 and ETV5), and the transcriptional regulator YY1 were equally represented in SCs and fibroblasts (Fig. 5a,c), and that Oct7/Brn2 (POU3F2) rather than Oct6 (POU3F1) was the prevalent POU3 isoform in human SCs (Fig. 5b).