Novella I S, Elena S F, Moya A, Domingo E, Holland J J
Department of Biology, University of California, San Diego, La Jolla 92093-0116, USA.
J Virol. 1995 May;69(5):2869-72. doi: 10.1128/JVI.69.5.2869-2872.1995.
Genetic bottlenecks are important events in the genetic diversification of organisms and colonization of new ecological niches. Repeated bottlenecking of RNA viruses often leads to fitness losses due to the operation of Muller's ratchet. Herein we use vesicular stomatitis virus to determine the transmission population size which leads to fitness decreases of virus populations. Remarkably, the effective size of a genetic bottleneck associated with fitness loss is greater when the fitness of the parental population increases. For example, for starting virus populations with low fitness, population transfers of five-clone-to-five-clone passages resulted in a fitness increase. However, when a parental population with high fitness was transferred, 30-clone-to-30-clone passages were required simply to maintain fitness values.
遗传瓶颈是生物遗传多样性和新生态位定殖过程中的重要事件。RNA病毒反复经历瓶颈效应往往会因缪勒棘轮效应导致适应性损失。在此，我们利用水疱性口炎病毒来确定导致病毒群体适应性下降的传播群体大小。值得注意的是，当亲代群体的适应性增加时，与适应性损失相关的遗传瓶颈的有效大小会更大。例如，对于适应性较低的起始病毒群体，五克隆到五克隆传代的群体转移导致适应性增加。然而，当转移具有高适应性的亲代群体时，仅需30克隆到30克隆传代就能维持适应性值。
