Identification of novel variants in PPT1 gene. a Illustrative representation of the distributions of the novel variants identified in Indian NCL1 patients investigated in this study. b Sanger sequencing discovered one missense variant (p.Cys45Arg) in exon 2, two missense variants (p.Pro238Leu and p.Val236Gly) in exon 7, and one frameshift variation (p.Glu178Asnfs*13) in exon 5 of PPT1 gene. The common variant p.Pro238Leu was identified in 44% of the patients. The point of variation is indicated by an arrow. c The multiple alignment of the protein sequence surrounding the novel variants against various orthologous sequence revealed the conservative status of the wildtype residues (marked red).