FALS with Gly72Ser mutation in SOD1 gene: Report of a family including the first autopsy case

Clinical information on familial amyotrophic lateral sclerosis (FALS) with Gly72Ser mutation in the Cu/Zn superoxide dismutase-1 (SOD1) gene has been limited and autopsy findings remain to be clarified. We describe one Japanese family with ALS carrying Gly72Ser mutation in the SOD1 gene, in which autopsy was performed on one affected member. The autopsied female patient developed muscle weakness of the left thigh at age 66 and showed transient upper motor neuron signs. She died of respiratory failure 13 months after onset without artificial respiratory support. There were no symptoms suggesting bladder or rectal dysfunction throughout the clinical course. Her brother with ALS was shown to have Gly72Ser mutation in the SOD1 gene. Histopathologically, motor neurons were markedly decreased throughout the whole spinal cord, whereas corticospinal tract involvement was very mild and was demonstrated only by CD68 immunohistochemistry. Degeneration was evident in the posterior funiculus, Clarke's nucleus, posterior cerebellar tract, and Onuf's nucleus. Neuronal hyaline inclusions were rarely observed in the neurons of the spinal cord anterior horn including Onuf's nucleus, and were immunoreactive for SOD1. To date, neuron loss in Onuf's nucleus has hardly been seen in ALS, except in the patients showing prolonged disease duration with artificial respiratory support. Involvement of Onuf's nucleus may be a characteristic pathological feature in FALS with Gly72Ser mutation in the SOD1 gene.