New phenotype of RTN2-related spectrum: Complicated form of spastic paraplegia-12.

In this study, we identified three cases with complicated SPG12 due to three novel RTN2 mutations, respectively, presenting various phenotypes: classic SPG symptoms with (1) visual abnormalities and sphincter disturbances or (2) seizures. The phenotypic heterogeneity might arise from the abnormal subcellular localization of mutant Reticulon-2 and improper ER morphogenesis, revealing the RTN2-related spectrum is still expanding.