Do genetic mutations really occur at random spots along the genome, as researchers have long supposed? Maybe not, according to a study published online today (January 13) in Proceedings of the Royal Society B, which proposes a mechanism for how new mutations might preferentially form around existing ones.
"The idea is quite interesting," said evolutionary geneticist Maud Tenaillon of the University of California, Irvine, who was not involved in the research. "I think it could be a good explanation for [mutational] hotspots." But, she cautioned, the support for this hypothesis so far falls solely on a somewhat incomplete theoretical model. Single nucleotide polymorphisms (SNPs) exist in clusters of varying size and density across the genome. Despite this non-random distribution, scientists believed for many years that these so-called mutational hotspots were the product of natural selection and other post-mutational processes, and that the mutations occurred at random. However, "in last two ...
