The impact of local population genetic background on the spread of the selfish element Medea‐1 in red flour beetles

摘要

Selfish genetic elements have been found in the genomes of many species, yet our understanding of their evolutionary dynamics is only partially understood. A number of distinct selfish elements are naturally present in many populations of the red flour beetle ( ). Although these elements are predicted by models to increase in frequency within populations because any offspring of a ‐bearing mother that do not inherit at least one allele will die, experiments demonstrating an increase in a naturally occurring element are lacking. Our survey of the specific element M , in the United States showed that it had a patchy geographic distribution. From the survey, it could not be determined if this distribution was caused by a slow process of M colonization of discrete populations or if some populations lacked M because they had genetic factors conferring resistance to the mechanism. We show that populations with naturally low to intermediate M frequencies likely represent transient states during the process of spread. Furthermore, we find no evidence that genetic factors are excluding M from US populations where the element is not presently found. We also show how a known suppressor of can impair the increase of M in populations and discuss the implications of our findings for pest‐management applications of elements.