Morquio A syndrome due to Maternal Uniparental Isodisomy of the telomeric end of chromosome 16

► First case of Lysosomal Storage Disease due to Maternal Uniparental Isodisomy. ► First case reported homozygote for p.Cys79Tyr mutation affecting GALNS active site. ► The possibility of UPD has relevant implications for genetic counseling.