NF1 may refer to: Neurofibromatosis type I, a genetic disorder that can cause tumors (can be cancerous) and other health effects such as vision impairment, imbowed legs, and joint pain. Neurofibromin 1, a protein associated with the disorder above. Nuclear factor 1, a transcription factor. NF-1, a variant of the AA-52 machine gun rechambered for 7.62 NATO ammunition. NF1 ( NGSFF/M.3), a specification for internally mounted expansion cards