BSCL2 S90L mutation in a Chinese family with Silver syndrome with a review of the literature.

Silver syndrome/spastic paraplegia 17 is an autosomal dominant, complicated hereditary spastic paraparesis in which spasticity of the legs is accompanied by amyotrophy of the hands and occasionally also the lower limbs. Heterozygous mutations of its causative gene, the Berardinelli-Seip congenital lipodystrophy gene, have a broader spectrum of phenotypes including Silver syndrome, distal hereditary motor neuropathy type V and Charcot-Marie-Tooth disease type 2. We report a Chinese family carrying the S90L mutation with Silver syndrome and discuss our literature review of the clinical phenotypes of S90L. Most reported patients (21 of 26) with this mutation showed a phenotype of Silver syndrome. The S90L mutation is predominantly associated with Silver syndrome.