Many pharmacologic advances involve creating compounds that bind and disable proteins. Such compounds include propranolol, which blocks the β-adrenergic receptor; cimetidine, which blocks the H2 receptor; calcium-channel blockers; angiotensin-converting–enzyme inhibitors; and inhibitors of the H+/K+–ATPase pump. A new way to block protein function is to prevent the translation of messenger RNA (mRNA) into protein.If the nucleic acid sequence encoding a protein is known, molecules can be designed to bind the corresponding mRNA, thereby inhibiting the production of the protein (Figure 1). The nucleotide sequence of DNA or RNA that contains the information for the amino acid sequence of . . .