Clinical and genetic study of a Brazilian family with spastic paraplegia (SPG6 locus).

We describe a Brazilian family in which inheritance of a G106R mutation in the SPG6 gene (also know as NIPA1) resulted in an autosomal dominant form of hereditary spastic paraplegia (ADHSP). Clinical investigations indicated that this family has a pure form of spastic paraplegia. All patients presented with gait difficulty in their twenties, progressing to frank spastic paraplegia during the next decade. Our report further supports evidence that mutations in SPG6 cause ADHSP.