One of the earliest proposed pre-RNA candidates is the flexible nucleic acid (FNA) structure based on the mixed acetal aminal of fomryl glycerol FNA achieves dramatic stereochemical simplification by formally deleting the 2.CHOH group of RNA, thereby replacing the four RNA stereocenters with a single (pro)stereocenter. Despite the documented inability of FNA to form stable duplexes with DNA flexible nucleoside triphosphates (fNTPS) are substrates for DNA polymerases. Consistent with early predictions, FNA chirality is unimportant as polymerases accept both (S)-and (R)-INTP antipodes. These results provide a renewed basis for positing FNA as a viable informational molecule.