Is. Novella et al., REPEATED TRANSFER OF SMALL RNA VIRUS POPULATIONS LEADING TO BALANCED FITNESS WITH INFREQUENT STOCHASTIC DRIFT, MGG. Molecular & general genetics, 252(6), 1996, pp. 733-738
The population dynamics of RNA viruses have an important influence on
fitness variation and, in consequence, on the adaptative potential and
virulence of this ubiquitous group of pathogens. Earlier work with ve
sicular stomatitis virus showed that large population transfers were r
eproducibly associated with fitness increases, whereas repeated transf
ers from plaque to plaque (genetic bottlenecks) lead to losses in fitn
ess. We demonstrate here that repeated five-plaque to five-plaque pass
age series yield long-term fitness stability, except for occasional st
ochastic fitness jumps. Repeated five-plaque passages regularly altern
ating with two consecutive large population transmissions did not caus
e fitness losses, but did limit the size of fitness gains that would o
therwise have occurred. These results underscore the profound effects
of bottleneck transmissions in virus evolution.