Detection of inversion with breakpoints in

Introduction: Mucopolysaccharidosis type VI (MPSVI), an autosomal recessive lysosomal storage disorder caused by pathogenic variants in Methods: Whole-exome sequencing (WES) and whole genome sequencing (WGS) were performed in a Chinese family having a boy with suspected diagnosis of MPS with macrocephaly, coarse facial features, broad forehead, thick lips, frontal bossing, craniosynostosis, blue spots, frequent upper respiratory infections, inguinal hernia, and dysostosis multiplex. Lysosomal enzymatic assays for leucocytes were used to assess the activity of arylsulfatase B of the boy's leucocytes. Sanger sequencing and karyotyping analysis were used to validate the variants identified in the boy and his parents. Results: This boy diagnosed with MPSVI based on clinical phenotypes and laboratory biochemical assays, and WES identified only a maternally inherited missense variant, c.908G>T (p.Gly303Val), in the Disscussion: This study reminds us that WGS should be done when WES failed to achieve a molecular diagonosis, and it also underscores the importance of WGS especially in cases of high clinical suspicion.