Abstract
DNA and RNA, by focusing on their unique molecular properties, have transcended their role as carriers of genetic information in life and pioneered new application fields such as molecular robotics and molecular computing. However, as these technologies advance, the limitations inherent in natural nucleic acids and their ecosystems are increasingly becoming apparent as barriers to further application. To overcome these constraints, efforts to create artificial nucleic acids using chemical synthesis are underway and are now reaching a new stage of development. This paper proposes a concept of ultimate nucleic acid, "Omega Nucleic Acids (ΩNA)," as a thought experiment. We discuss the specifications required for this molecule, its implementable functions and approaches, and the construction of an ecosystem centered around ΩNA. By working backward from the characteristics of known natural and artificial nucleic acids, while envisioning next-generation artificial systems and applications in extreme environments, we aim to explore new approaches to nucleic acid chemistry and provide guidelines for constructing innovative artificial molecular systems.