TFG associated hereditary spastic paraplegia: an addition to the phenotypic spectrum.

Hereditary spastic paraplegias (HSPs) constitute movement disorders with extreme lower limb spasticity caused by axonopathies of the upper motor neurons. We describe two siblings affected with a recessive form of movement disorder. Whole-exome sequencing revealed a homozygous missense mutation c.64 C>T (p.Arg22Trp) in TFG as cause of the disorder. Comparison of the phenotype of the patients of this study, with that reported previously, revealed differences in the severity of the disorder as well as new clinical findings. These include presence of clonus, undeveloped speech, and sleep disturbances. Our findings extend the phenotypic spectrum associated with the TFG mutations in HSP.