A clinical study of a large inbred kindred with pure familial spastic paraplegia

Background and objectives: Spastic paraplegia, an uncommon neurodegenerative disorder with phenotypic and genotypic heterogeneity, is mainly characterized by progressive weakness and spasticity of the lower limbs. We here present a large inbred family with pure familial spastic paraplegia outlining the clinical picture, the age at onset and the possible mode of inheritance. Methods: This family was ascertained through two probands after which we structured an extended 10 generation pedigree. We examined 43 available family members to identify affected individuals based on fixed criteria. The clinical presentation and phenotypic specifics of this disease were studied in the affected members. We analyzed the possible mode of inheritance and the age at onset in this family. Results: This 10 generation family reported about 50 affected individuals distributed over 5 consecutive generations. We identified 13 affected individuals out of the examined 43 and five individuals were classified as probably affected. We noticed the clinical specifics of this disorder in this family and identified some unique features not described in previous reports. Discussion and conclusion: The mode of inheritance is either autosomal recessive or autosomal dominant with incomplete penetrance or variable expression of the age at onset. The age at onset seems to decrease with successive generations, either due to a true anticipatory phenomenon or to increased awareness. The unique features of this disorder in this family are discussed.