4 RNA WORLD RNA was the first genetic material. There are evidences to suggest that essential life processes, such as metabolism, translation, splicing, etc. evolved around RNA. RNA used to act as a genetic material as well as a Catalyst. There are some important biochemical reactions in systems that are catalyzed by RNA catalysts and not by proteinaceous enzymes (e.g., splicing). RNA being a catalyst was reactive and hence unstable . Therefore, DNA has evolved from RNA with chemical modifications that make it more stable. DNA being double stranded and having complementary strand further resists changes by evolving a process of repair. RNA is an adapter, structural molecule and in some cases catalytic. Thus, RNA is better material for transmission of information. Fig: A schematic representation of the classical RNA world hypothesis. Initially, synthesis and random polymerisation of nucleotides result in pools of nucleic acid oligomers, in which template-directed nonenzymatic replication may occur. Recombination reactions result in the generation of longer oligomers.