A novel nonsense MPS VI mutation in a south Moroccan patient

A 12-years-old, Moroccan child with a history of skeletal deformities, gait disorder, Short stature, valvulopathy, facial dysmorphy, corneal opacity, umbilical hernia, and hepatomegaly. He has onset from birth, delayed first milestones (setting, gait, and language) and severe dysostosis multiplex. Elevated urinary glycosaminoglycans concentration was found, enzymatic assays show a low level of ARSB, genetic testing confirmed a diagnosis of Mucopolysaccharidosis type VI with a novel mutation in ARSB gene. There is a homozygous frameshift nonsense mutation by two thymine deletion in 770 and 771 codons (c. [770_771del TT]; [770_771del TT]). This is the first case and mutation of Mucopolysaccharidosis type VI detected in south Morocco. Keywords: : mucopolysaccharidosis VI; ARSB gene; nonsense mutation; ERT