Neurofilaments are the 10nm or intermediate filament proteins found specifically in neurons, and are composed predominantly of three major proteins called NF-L, NF-M and NF-H. NF-L is the neurofilament light or low molecular weight polypeptide and runs on SDS-PAGE gels at about 68kDa. Antibodies to NF-L are useful for identifying neuronal cells and their processes in tissue sections and in tissue culture. Mutations in the protein coding region of the human NF-L gene cause some forms of Charcot-Marie-Tooth disease.