Stochastic clonal dynamics and genetic turnover in exponentially growing populations

TL;DR

This paper analyzes how reproductive fluctuations influence long-term genetic diversity in exponentially growing populations, providing analytical tools to predict clone extinction and infer underlying population dynamics.

Contribution

It introduces an analytical framework combining first step analysis and stochastic birth-death processes to study genetic turnover in growing populations.

Findings

Derived probabilities of clone extinction under reproductive fluctuations

Validated analytical results with numerical simulations

Showed how genetic turnover can infer population growth rates

Abstract

We consider an exponentially growing population of cells undergoing mutations and ask about the effect of reproductive fluctuations (genetic drift) on its long-term evolution. We combine first step analysis with the stochastic dynamics of a birth-death process to analytically calculate the probability that the parent of a given genotype will go extinct. We compare the results with numerical simulations and show how this turnover of genetic clones can be used to infer the rates underlying the population dynamics. Our work is motivated by growing populations of tumour cells, the epidemic spread of viruses, and bacterial growth.