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KEY DRIVERS OF SWARMS. "Two key parameters that explain the biological relevance of the rapid formation of mutant swarms during viral replication are the rate at which mutations are introduced during RNA genome copying, and the genome size." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

REPLICATION ERRORS. "The match between events at the cellular and epidemiological level lies in the error-prone replicative machinery that manifests in every environment in which viruses multiply." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

MUTANT PANDEMICS. "Mutant swarms are established within single infected cells and cell clusters and in infected organisms during disease episodes, outbreaks, epidemics and pandemics." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

MILLIONS OF PROGENY. "RNA viruses have tremendous reproductive capacity, generating thousands of progeny per genome. Despite frequent bottleneck events, a total population of millions of viruses in an infected host is not uncommon." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

GIANT POPULATIONS. "An important aspect of the quasispecies concept is that the large size of virus populations enables positive and negative interactions between individual viruses to establish a quasi-equilibrium of the variant proportions. Genetic variation is generated by the accumulation of mutations during replication and their re-arrangement by genetic recombination, and genome segment reassortment in the case of segmented genomes." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

DARWINIAN VIEW. "Viral quasispecies are currently defined as collections of closely related viral genomes subjected to a continuous process of genetic variation, competition among the variants generated, and selection of the most fit distributions in a given environment." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

FIRST LIFE FORMS. "The quasispecies concept originated in a theoretical formulation of molecular evolution that emphasized error-prone replication of simple RNA or RNA-like replicons as an essential feature of self-organization and adaptability of primitive life forms." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn

QUASISPECIES. "Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of selection." http://mmbr.asm.org/content/76/2/159.short View in LinkedIn

SO ENDS this first of two weekends on mutant RNA viral swarms or quasispecies. These highly proliferative, highly mutating populations of viruses offer possible insights into a RNA-first origin of life scenario. These shape-shifting populations evolve very fast, adapt to new circumstances, and show dramatic phenotypic flexibility. Next weekend we look at some of the clinical implications of these viruses. View in LinkedIn

INTERACTIONS. "It is worth noting that these interactions occur among different genomes, so that the effects are different from those of positive or negative epistasis that are established between mutations within the same genome." http://www.sciencedirect.com/science/article/pii/S0042682215001580 View in LinkedIn