Interestingly, co-injection of recombinant human iduronate-2-sulfatase (Elaprase; idursulfase) combined with z-ids-MO could rescue the defects caused by z-ids knockdown, suggesting that (1) zebrafish can serve as an in vivo model to study the effect of IDS enzymatic activity on the phenotype and (2) zebrafish can serve as a novel tool to better understand the pathogenesis of lysosomal storage disorder, providing a new method of drug screening for MPS II [82]. The gene discussed is IDS; the disease is lysosomal storage disease.