Described herein are novel divalent nucleobases that each bind two nucleic acid strands, matched or mismatched when incorporated into a nucleic acid or nucleic acid analog backbone (a genetic recognition reagent, or genetic recognition reagent). In one embodiment, the genetic recognition reagent is a peptide nucleic acid (PNA) or gamma PNA (?PNA) oligomer. Uses of the divalent nucleobases and monomers and genetic recognition reagents containing the divalent nucleobases also are provided.