Abstract: Described herein are divalent nucleobases that each binds two nucleic acid strands, matched or mismatched when incorporated into a nucleic acid or nucleic acid analog backbone, such as in a ?-peptide nucleic acid (?PNA). Also provided are genetic recognition reagents comprising one or more of the divalent nucleobases and a nucleic acid or nucleic acid analog backbone, such as a ?PNA backbone. Uses for the divalent nucleobases and monomers and genetic recognition reagents containing the divalent nucleobases also are provided.