GFRA2 and neurofibromatosis type 1: Functional genomics assessments verified a consistently high level of RET and NTRN transcripts among s-cNF from different NF1 patients, as well as moderate to high levels for GFRA2, GFRA3, and ARTN. Compared to normal skin, relative transcripts for NTRN, GFRA2, and GFRA3 were significantly higher in s-cNF whereas c-Ret was similar.