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Research was conducted to examine the information transfer from HNA oligomers to RNA by nonenzymatic template-directed synthesis. Oligomerization reactions were carried out on HNA, C4XC4 templates and compared them with reactions on the corresponding DNA C4XC4 templates. Results indicate that HNA heterosequences seem to be superior to the corresponding DNA heterosequences in facilitating synthesis of complementary oligonucleotides from nucleoside-5'-phosphoro-2-methyl imidazolides.

The oligomerization of guanosine 5'-phosphoro-2-methylimidazole (2-MeImpG) has been compared with that of Pb2+-catalyzed oligomerization of guanosine 5'-phosphoroimidazole (ImpG) on decacytidylate templates of hexitol nucleic acid (HNA) (hC10), RNA (C10) and DNA (dC10). HNA is an analogue of DNA having the standard nucleoside bases but with a phosphorylated 1,5-anhydrohexitol backbone. Results indicated that the oligomerization of 2-MeImpG produces similar patterns of products on hC10, C10 and dC10 templates. The reaction is more efficient on the hC10 template as is the Pb2+-catalyzed oligomerization of ImpG.

Three popular hypotheses attempt to explain the origin of prebiotic molecules: synthesis in a reducing atmosphere, input in meteorites and synthesis on metal sulfides in deep-sea vents. It is not possible to decide which is correct. It is also unclear whether the RNA world was the first biological world or whether some simpler world preceded it.

DNA-peptide nucleic acid (PNA) chimeras can be formed efficiently through ligation on both PNA and DNA templates. Formation of 3'-phosphoramidate bonds, 5'phosphoramidate bonds, 5'-ester bonds and 5'-amide bonds occur at varying speeds. The 3'-phosphoramidate bonds formed the fastest and 5'-ester bonds formed the slowest. The initial rate of [32P]-labeled DNA-to-PNA ligation on a template relies on the extent to which the DNA is present in a ternary complex with the template and the substrate PNA and on the rate of ligation within the ternary complex.

The possibility of a peptide nucleic acid (PNA) world as the precursor to the RNA world is supported by the ability of RNA oligonucleotides to facilitate complementary PNA strand synthesis and vice versa. This ability may have prevented information loss in the transition between the two genetic system.