Whole Exome Sequencing Reveals a BSCL2 Mutation Causing Progressive Encephalopathy with Lipodystrophy (PELD) in an Iranian Pediatric Patient

Background: Progressive encephalopathy with or without lipodystrophy is a rare autosomal recessive childhoodonset seipin-associated neurodegenerative syndrome, leading to developmental regression of motor and cognitive skills. In this study, we introduce a patient with developmental regression and autism. The causative mutation was found by exome sequencing. Methods: The proband showed a generalized hypertonia and regression of all developmental milestones. Based on the advantages of next-generation sequencing (NGS), whole exome sequencing (WES) was requested. The functional significance of variants was evaluated by NGS-specific prediction servers. Sanger sequencing was used for segregation analysis in the family. Results: There was no specific sign in the clinical and paraclinical investigations of the patient to establish a conclusive clinical diagnosis. WES detected a known homozygous nonsense mutation in BSCL2 (NM_001122955.3:c. 985C>T; p.Arg329*). The variant is segregating in the pedigree with an autosomal recessive pattern. Conclusion: Exome sequencing is a robust method for identifying the candidate gene variants in Mendelian traits.