Assays for screening small-molecule compounds for their ability to induce translational readthrough of stop codons are disclosed. The assays utilize a dual enzymatic reporter plasmid system, wherein one reporter acts as an internal standard and the second reporter measures the translational recoding event induced by the small-molecules. The genetic sequence mutations of interest are placed on the plasmid between the two reporter genes and the plasmids are transfected into tissue culture cells. The cells are then grown in the presence of varying amounts of small-molecule compounds and the induction of translational readthrough is measured.
 This invention was made with government support under Department of Energy grant DEFG03-99ER62732 and National Institutes of Health grant RO1-GM48152-05. The government has certain rights in the invention.