The utilization of rodents, especially mice, as animal models has allowed scientists to explore and discover key aspects of many human and animal diseases. Mice, like other living organisms, have an intrinsic genetic drive to change. With each passing generation, spontaneous mutations can potentially develop in vivo from DNA repair processes or during meiosis. It is important to understand and recognize that inbred strains are not exempt from this biological phenomenon. In a recently-published Cell Reports paper, the authors discovered that their transgenic mouse’s phenotype was not a result of the genetic changes they induced, but resulted from a spontaneous mutation that disrupted the function of Dock2 which was present in the C57BL/6NHsd (B6/NHsd) substrain they used for backcrossing. The authors speculated that the B6/NHsd substrain acquired this mutation either through genetic drift or genetic contamination from the 129 inbred strain at a remote time during their history. These findings highlight the impact that substrain divergence can have on research when spontaneous mutations accumulate and go unnoticed. Moreover, this paper demonstrated significant flaws within the vendor’s genetic stability program. This seminar will discuss the main findings of this paper, define genetic drift and its implications on research, in addition to ways vendors and investigators can mitigate the impact of genetic drift on their mice colonies and research.
This program is for the Tri-Institutional research community.