Related Experiment Video
Updated: Jul 16, 2026

A Genetic Screen to Isolate Toxoplasma gondii Host-cell Egress Mutants
Published on: February 8, 2012
Dynamics of escape mutants
Maria Conceição Serra1, Patsy Haccou
1Department of Mathematics, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. mcserra@math.uminho.pt
Abstract:
We use multi-type Galton-Watson branching processes to model the evolution of populations that, due to a small reproductive ratio of the individuals, are doomed to extinction. Yet, mutations occurring during the reproduction process, may lead to the appearance of new types of individuals that are able to escape extinction. We provide examples of such populations in medical, biological and environmental contexts and give results on (i) the probability of escape/extinction, (ii) the distribution of the waiting time to produce the first individual whose lineage does not get extinct and (iii) the distribution of the time it takes for the number of mutants to reach a high level. Special attention is dedicated to the case where the probability of mutation is very small and approximations for (i)-(iii) are derived.
Related Concept Videos
Mutation, Gene Flow, and Genetic Drift
Escape Velocity
To calculate the escape velocity, it is assumed that no energy is lost to any frictional forces. In practice, a satellite launched from...
Lethal Alleles
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Evolution of New Traits in Microbes
Spontaneous and Induced Mutations

