GNC hypothesis

GNC hypothesis or GNC-SNS primeval genetic code hypothesis refers to a hypothesis about the origin of genes. While almost all of the organisms on present Earth shares the universal genetic code, in GNC hypothesis it is argued that two primeval genetic codes preceded the present genetic code as follows.

This hypothesis was first proposed by Kenji Ikehara at Nara Women's University.

GNC hypothesis is based on the following facts.

Ikehara, Kenji; Omori, Yoko; Arai, Rieko; Hirose, Akiko (2002). "A Novel Theory on the Origin of the Genetic Code: A GNC-SNS Hypothesis". Journal of Molecular Evolution. Springer-Verlag. 54: 530–538. doi:10.1007/s00239-001-0053-6. 

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