• Androgen receptors have been demonstrated in both cranial nerve and spinal motor neurons. This article proposes that amyotrophic lateral sclerosis (ALS) may be a disease in which androgen receptors in motor neurons are lost or not functioning. This is suggested by the male-to-4 female ratio of the disease, the age of onset, and the sparing of neurons of cranial nerves III, IV, and VI that coincidentally lack androgen receptors. The hypothesis is that ALS may be due to a loss of androgen receptors that results in an inability to respond to a variety of Insults Including axonal damage.