Variations in polymer fitness at elevated mutation rates
โ Scribed by Brian K. Davis
- Book ID
- 104271952
- Publisher
- Springer
- Year
- 1991
- Tongue
- English
- Weight
- 825 KB
- Volume
- 53
- Category
- Article
- ISSN
- 1522-9602
No coin nor oath required. For personal study only.
โฆ Synopsis
Two series expressions were obtained that give the first and second order rates of change in population fitness during competitive replication at elevated mutation rates. At their zeroerror limit, the respective power series reduces to the second (Fisher's theorem) and third moments of the fitness distribution. The first series maximized the variation in mean polymer fitness, for a given amount of population covariance. From experimental results reported by Splegelman's group on evolution in vitro among Qfl RNA variants, it was demonstrated: (i) terms in the (second) series fall-off at a rate broadly equal to the replicase error (e ~-10-4); (ii) the rate of change in mean RNA fitness (polymer formation rate constant) corresponds to the variance in fitness; and (iii) agreement exists between second order rate changes in fitness and the third moment (skewness) regression line, extending over 20 successive replication reactions. The impact of these findings on the standard model of evolution has been discussed.
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