Modeling the diffusion of genes in a population


Evolution can be defined as a change in the heritable component of an organism, mostly mediated by selection. Most living organisms are evolving based on the selection pressure imposed on them. The effects of evolution acting at the individual level, results in discernible changes at the population level. Almost all coding regions in our DNA are under selection pressure. Positive selection pressure on a gene for very long durations could result in fixation of the gene in the population, while a negative selection pressure on a gene, would result in a decrease or complete removal of the gene in the population. Variations of the gene that confer an organism with greater fitness are positively selected and the ones which confer the organism with lesser fitness are negatively selected. The main objective of this project is to model the spread of a gene in a population based on the selection pressures applied, using diffusion as a tool. The factors which are considered in this study are Generation rate and Consumption rate (birth and death rates) of the population. The diffusion of a gene, under different selection possibilities is modeled and studied across 100 generations.