Recombination facilitates neofunctionalization of duplicate genes via originalization

BACKGROUND: Recently originalization was proposed to be an effective way of duplicate-gene preservation, in which recombination provokes the high frequency of original (or wild-type) allele on both duplicated loci. Because the high frequency of wild-type allele might drive the arising and accumulating of advantageous mutation, it is hypothesized that recombination might enlarge the probability of neofunctionalization (P(neo)) of duplicate genes. In this article this hypothesis has been tested theoretically. RESULTS: Results show that through originalization recombination might not only shorten mean time to neofunctionalizaiton, but also enlarge P(neo). CONCLUSIONS: Therefore, recombination might facilitate neofunctionalization via originalization. Several extensive applications of these results on genomic evolution have been discussed: 1. Time to nonfunctionalization can be much longer than a few million generations expected before; 2. Homogenization on duplicated loci results from not only gene conversion, but also originalization; 3. Although the rate of advantageous mutation is much small compared with that of degenerative mutation, P(neo )cannot be expected to be small.