Study suggests evolution is informed and not completely random

A new study carried out by researchers from Ghana and Israel is challenging the long-established notion that the genetic mutations driving evolution are entirely random. The research — published in the Proceedings of the National Academy of Sciences (PNAS) — suggests that evolutionarily critical mutations can arise more frequently within the specific populations where they provide an advantage, such as protection from disease.

For a long time, the major principle of evolutionary biology has been that mutations are simple random accidents, and natural selection determines which ones are beneficial. The new research — led by Professor Adi Livnat of the University of Haifa — provides evidence that directly challenges this principle.

Using a new detection method called MEMDS, the team examined the de novo (new) origination rate of a specific mutation in the APOL1 gene. This mutation protects against African sleeping sickness but increases the risk of kidney disease in homozygotes. The researchers found that the mutation originates de novo significantly more frequently in sperm samples acquired from Ghanaian donors than samples from northern European donors. This result solidifies a previous finding by the research team of the anti-malarial HbS mutation, which was found to arise more often in sub-Saharan Africans.

Based on these findings, the scientists propose a new theory of “natural simplification.” It suggests that while the external factor of natural selection exists, there is also an internal force that uses the information accumulated in the genome over generations to guide which mutations are likely to occur. This redefines mutations not as disjointed accidents, but as meaningful events in a bigger, long-term process.