LAUSR

Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous neurodegenerative disorder, which is characterized by the spasticity of the lower limbs due to pyramidal tract dysfunction. More than 70 different genetic HSP forms have been reported [1]. Spastic paraplegia-30 (SPG30; OMIM #610357) is an autosomal recessive form of HSP and is characterized by childhood-onset, progressive spastic paraplegia [2–4]. SPG30 has been shown to be caused by a homozygous missense mutation in KIF1A [3,4]. KIF1A encodes the neuronspecific motor protein involved in anterograde axonal transport [5]. Spinocerebellar ataxia 31 (SCA31; OMIM #117210) is an autosomal dominant, adult-onset neurodegenerative disorder that exhibits predominantly pure cerebellar ataxia and is caused by an abnormal pentanucleotide repeat expansion in an intron shared by BEAN and TK2 [6]. Here we describe a patient with SPG30, who is carrying a novel homozygous KIF1A mutation and is in a Japanese family in which multiple members are affected with SCA31.