Interestingly, knockout of the mouse ortholog Crmp1 leads to impairment in neuronal migration, proliferation and spine density, culminating in impaired spatial memory and electrophysiological stimuli transmission.39, 40, 41 This gene has, in fact, been proposed as a potential therapeutical target for Alzheimer disease and amyotrophic lateral sclerosis.42 The gene discussed is CRMP1; the disease is early-onset autosomal dominant Alzheimer disease.