 mRNA rescue experiments can often restore the wild @-@ type phenotype to the embryos and provide evidence for the specificity of a Morpholino . In an mRNA rescue , a Morpholino is co @-@ injected with an mRNA that codes for the same protein that the <unk> is targeted to knock down . However , the rescue mRNA has a modified 5 ' -UTR ( untranslated region ) so that the rescue mRNA contains no target for the Morpholino but the rescue mRNA 's coding region encodes the protein of interest . Translation of the rescue mRNA replaces production of the protein that was knocked down by the Morpholino . Since the rescue mRNA would not affect phenotypic changes due to modulation of off @-@ target gene expression by the Morpholino , this return to wild @-@ type phenotype is further evidence of Morpholino specificity . 
