NF1 and Pseudoarthrosis: To determine the underlying mechanism driving human pseudoarthrosis, we first performed transcriptome analyses of primary control cells (i.e., NF1+/–) cultured from unaffected bone (N = 7 patients) and primary mosaic (i.e., mixed NF1+/– and NF1–/–) cells cultured from pseudarthrosis fractures (N = 13 patients) from patients with clinical diagnoses of NF1.