Background: Hereditary spastic paraplegia (HSP) is a neurodegenerative disease that is characterized by progressive weakness and spasticity of the lower extremities; HSP can present as complicated forms with additional neurological signs. More than 70 disease loci have been described with different modes of inheritance.
Methods: In this study, nine subjects from a Chinese family that included two individuals affected by HSP were examined through detailed clinical evaluations, physical examinations, and genetic tests. Targeted exome capture technology was used to identify gene mutations.
Results: Two novel compound heterozygous mutations in the SPG 11 gene were identified, c.4001_4002insATAAC and c.4057C>G. The c.4001_4002insATAAC mutation leads to a reading frame shift during transcription, resulting in premature termination of the protein product. The missense mutation c.4057C>G (p.H1353D) is located in a highly conserved domain and is predicted to be a damaging substitution.
Conclusions: Based on the results described here, we propose that these novel compound heterozygous mutations in SPG 11 are the genetic cause of autosomal recessive HSP in this Chinese family.
Keywords: SPG 11; Genetics; Hereditary spastic paraplegia; Mutation; Targeted exome capture; Thin corpus callosum.