新規のSPG4遺伝子変異を認めた家族歴のない純粋型遺伝性痙性対麻痺症例の臨床像

Spastic Paraplegia Caused by a Novel Mutation in the Spastin Gene (1207C→G, P361R) ― Clinical Features of a Patient without Family History

はじめに

　遺伝性痙性対麻痺（hereditary spastic paraplegia: HSP）は，緩徐進行性の痙性対麻痺を主徴とする遺伝性神経変性疾患群であり，HSPの原因遺伝子座は現在のところ30種類同定されている。われわれは，新規のspastin遺伝子変異を伴った家族歴のないSPG4症例を経験したので，その臨床像の詳細について報告する。なお，本症例の遺伝子変異については，別報^1）を参照されたい。

Abstract

　A 52-year-old man with no apparent family history of neurodegenerative diseases developed gait disturbance at age 47.　Neurological examination at aged 52 revealed spastic paraplegia, generalized hyperreflexia, decreased of vibration sense in the lower limbs, and pollakisuria.　Ocular symptoms, deafness, cerebellar ataxia, extrapyramidal signs, mental deterioration, dementia, peripheral neuropathy, retinal pigment degeneration, ichthyosis and syndactyly were absent.　MRI of the brain was normal.　A pure form of hereditary spastic paraplegia was diagnosed.　Genetic analysis revealed a novel missense mutation in the spastin gene (1207C→G, P361R).　The clinical features of this patient were consistent with those of patient with the pure form of SPG4.　Gene analysis should be considered for patients with spastic paraplegia even in the absence of any family history.