Viranoids

Viranoids are a theoretical concept in astrobiology and synthetic biology, representing a form of life or replicating entity that utilizes a non-nucleic acid genetic material. Unlike terrestrial life, which relies on DNA or RNA to store and transmit genetic information, viranoids would employ an alternative molecular system for heredity. The term itself is derived from "viral" and "oids," suggesting a resemblance to viruses in their replication strategy but with a fundamentally different biochemical basis.

The precise nature of viranoid genetic material is speculative. It could involve complex polymers or chemical structures not yet discovered or synthesized. Researchers in synthetic biology are exploring various alternative genetic polymers, such as peptide nucleic acids (PNAs) or threose nucleic acids (TNAs), as potential candidates for artificial genetic systems. These investigations, while not directly observing viranoids, contribute to understanding the theoretical possibility of life based on non-standard biochemistry.

The study of viranoids is primarily theoretical, aiming to expand our understanding of the boundaries of life and the potential diversity of life beyond Earth. If extraterrestrial life exists, it might not conform to Earth's genetic paradigm, and viranoids represent one such hypothetical alternative. The concept also has implications for origin-of-life research, suggesting that the DNA/RNA system may not be the only viable pathway for abiogenesis.