Figure 1.

Genetic information can be replicated in two ways. (A) For nucleic acid-based determinants, replication occurs through the polymerization of free nucleotides (light blue), using the sequence of bases in an existing polymer (dark blue) as a template. (B) For protein-based determinants, genetic information is encoded in quaternary structure. For the example shown here, a simple rectangle can be assembled with the subunits aligned along either their short or their long faces, leading to two distinct self-replicating polymers. Adapted from Caughey.¹⁴²