Two novel mutations in the Spastin gene of Chinese patients with hereditary spastic paraplegia.

Objective:   Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous group of neurodegenerative diseases. Mutations in the spastin (SPG4) gene are responsible for approximately 40% of autosomal dominant HSP (AD-HSP) and 6.5-18% of sporadic cases.

Methods:   Spastin mutations were screened in 11 AD-HSP families and 11 sporadic cases by direct sequencing and MLPA assay. Novel mutations were detected in 100 healthy controls by PCR-RFLP.

Results:   We identified seven different spastin mutations in five probands and one sporadic patient. Two of seven mutations were novel. The c.458delT was a pathogenic mutation, but the effect of c.1724 G>T remained unknown.

Conclusions:   This study allowed us to estimate the frequency of the SPG4 mutations in Chinese at 45% (5/11) in families with AD-HSP and 9% (1/11) in sporadic cases. In addition, our data showed p.T614I was not associated with congenital arachnoid cysts.