Now it’s my turn to be smug. In last month’s edition of Acts & Facts “Deputy Director for Life Sciences Research” Nathaniel Jeanson announced that he was investigating differential mutation rates as an explanation for the observed differences in sequence in the same gene in different species. His hypothesis was that God had, in effect, a pool of genes to choose from when he created life. All organisms that needed a specific gene would be given the same one, but the particular genes needed by each would vary. These originally identical genes would then diverge through mutations, with Jeanson using lower generation times as proxies for higher mutation rates. His original supporting evidence came in the form of the mitochondrial ATP-6 genes of the elephant, mouse, and fruit fly.
As I pointed out at the time there are a number of flaws in this hypothesis. For one – despite Jeanson’s claims to the contrary – this process would not necessarily create the observed hierarchy in sequence similarity. More importantly, however, the three animals analysed at that point just happened to have their evolutionary relatedness approximately agree with the predictions of Jeanson’s differential mutation rate model. I predicted that the mere insertion of a fourth animal would ruin the correlation, suggesting a turtle as a good test subject.
The ICR has not tested a turtle, but instead has analysed a large number of mammalian ATP-6 genes. Jeanson has written a new article for the November Acts & Facts edition: Bio-Origins Project Update, Evidence Against Differential Mutation Rates. Continue reading