amyotrophic lateral sclerosis 18
An autosomal dominant neurodegenerative disorder (OMIM:614808) affecting upper motor neurons in the brain and lower motor neurons in the brain stem and spinal cord, resulting in fatal paralysis. Sensory defects are absent.
Pathology Pallor of corticospinal tract due to loss of motor neurons, ubiquitin-positive inclusions within surviving motor neurons
Aetiology, amyotrophic lateral sclerosis Multifactorial, involving genetic and environmental factors; 5-10% of cases are inherited.
Molecular pathology Defects of PFN1, which encodes profilin 1, a protein that binds actin and alters the cytoskeleton in response to extracellular signals, cause amyotrophic lateral sclerosis 18.