Clinical characteristics and gene mutation analysis of a family with hereditary spastic paraplegia type 11

Abstract Background：Autosomal recessive spastic paraplegia with thinning of corpus callosum (ARHSP-TCC) is a complex hereditary spastic paraplegia. Spastic Paraplegia gene 11(SPG11) is the most common ARHSP-TCC. The study of SPG11 in China is small in scale, and only a few gene mutations have been reported . Case Presentation:We reported a family with ARHSP-TCC. The proband presented spastic gait and cognitive impairment. Brain MRI showed thinning of corpus callosum. The proband's brother shows only a spastic gait. A detailed history, physical examination, and supplementary examination were performed to rule out the acquired cause of spastic paraplegia. In order to identify pathogenic mutations, we used target sequence capture sequencing technology to detect HSP-related genes in family members, combined with Sanger sequencing verification, and found two new complex heterozygous mutations of SPG11: c.6738_6739insT and c.5934_5935insTAACCTGGAA. The codon of Glu2247 amino acid changed to stop codon (p.Glu2247Ter) and that of Val1979 amino acid changed to stop codon (p.Val1979ter), respectively. Bioinformatics analysis predicted that these mutations would result in a loss of protein function. Conclusions: We found two novel complex heterozygous mutations of SPG11 : c.6738_6739insT and c.5934_5935insTAACCTGGAA，which enriches the phenotype of SPG11 mutations.