Future studies should therefore examine utility of ourSSOs in thymic epithelial cells and β-cells that may provide a more naturalsystem for testing their impact on both exo- and endogenous proinsulin expression.Finally, similar antisense strategies may help reduce pervasive intron retention incancer cells resulting from somatic mutations of splicing factor genes, asillustrated by specific substitutions in the zinc finger domain of U2AF35 inmyeloproliferative diseases (78). The gene discussed is U2AF1; the disease is glycogen storage disease VI.