Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive muscular paralysis reflecting degeneration of motor neurons in the primary motor cortex, corticospinal tracts, brainstem and spinal cord. The disease is amyotrophic lateral sclerosis (MONDO_0004976). Also known as: ALS, Charcot disease, Lou Gehrig disease, Lou Gehrig's disease, motor neuron disease, bulbar.