PTCs have been identified in a large cohort of patients with MPS (Brooks et al 2006); in particular, ARSB mutational analysis in MPS VI patients has allowed to identify 16 different ARSB nonsense mutations (Human Gene Mutation Database; http://www.hgmd.cf.ac.uk/ac/index.php, last access on January 2012) which can be potential targets of stop codon read-through. This evidence concerns the gene ARSB and mucopolysaccharidosis type 6.