Fig. 2.

Mutational spectrum of SPAST gene in Chinese SPG4 patients. a Schematic representation of the mutational location in cDNA of SPAST gene detected in Chinese SPG4 patients (n = 272). The SPAST gene spans the region of ~ 90 kb of genomic DNA and contains 17 exons. Mutations detected in the current study are indicated in red characters. TM (57–79 amino acids), MIT (116–197 amino acids), MTBD (270–328 amino acids) and AAA cassette (342-599  amino acids) are highlighted. b Distribution of mutations are shown within 17 exons of SPAST gene. c The proportion of exon deletion and duplication spectrum. d The percentage of patients who carried micro mutations or exon deletion/duplication in SPAST gene