Every duplicated gene (or nuon), whether generated by recombination or retroposition can become an active gene, or part thereof, potentially giving rise to a variant or even a gene with novel function [...] Since such features have the option or potential of becoming functional in the course of evolution or, alternatively, may remain nonaptations, we will here introduce the term ›potaptation‹. It follows that any duplicated or amplified gene or nuon is a ›potogene‹ or ›potonuon‹.
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