The purpose of this pilot study was to assess whether G-CSF treatment in ALS patientsis feasible, and to explore potential subclinical effects of G-CSF on structuralcerebral abnormalities by using a combination of voxel-based morphometry (VBM) andwhole-brain, voxel-based diffusion tensor imaging (DTI) analysis. The gene discussed is CSF3; the disease is amyotrophic lateral sclerosis.