Fig. 1.

a Pedigree of family 1, with two affected siblings with Sandhoff disease (filled symbols). Genotype is shown in red under individuals (+, mutant; −, WT). * indicates samples available for analysis. The affected female was shown to be homozygous for the HEXB c.445 + 1G > T splice site variant. b Electropherogram showing the DNA sequence variant (HEXB c.445 + 1G > T) in a homozygous affected individual. c Schematic representation of HEXB exons and position of the genomic variant identified in this study. d-e Pedigrees of families 2 and 3, both from the Khyber Pakhtunkhwa province and with individuals affected with a neurodevelopmental disorder (filled symbols), within the same generation. Genotype is shown in red under individuals (+, mutant; −, WT). * indicates samples available for analysis. Six affected individuals were shown to be homozygous for the MBOAT7 c.758_778del; p.(Glu253_Ala259del) variant (f) Electropherogram showing the DNA sequence variant (MBOAT7 c.758_778del; p.(Glu253_Ala259del) in a homozygous affected individual (g) Schematic representation of MBOAT7 exons and positions of the genomic variant identified in this study