Spastic Paraplegia 32, Autosomal Recessive

Clinical Features

Stevanin et al. (2007) reported a consanguineous Portuguese family in which 3 sibs had slowly progressive complicated spastic paraplegia. The patients were first examined at ages 20 to 24 years but reported onset of difficulty walking at 6 to 7 years of age. Physical examination showed lower limb hyperreflexia, weakness, and spasticity at rest and while walking (with a stick), as well as extensor plantar responses and pes cavus. All had mild mental retardation and learning problems but were able to help their parents on the farm. Brain MRI of 2 patients showed thin corpus callosum, cortical and cerebellar atrophy, and pontine dysraphia. One patient with a history of alcohol abuse had peripheral neuropathy.

Mapping

By genomewide linkage analysis of a consanguineous Portuguese family with spastic paraplegia, Stevanin et al. (2007) identified a candidate locus, termed SPG32, on chromosome 14q12-q21 (maximum multipoint lod score of 3.74). Haplotype analysis delineated a 30-cM interval between D14S264 and D14S978. The region partially overlapped the initial locus for SPG3A (182600), but genetic analysis did not identify mutations in the atlastin gene (606439). Stevanin et al. (2007) noted that other SPG loci map to the same chromosome in the following order: 14qcen--SPG32--SPG3A--SPG28 (609340)--SPG15 (270700)--14qtel.