Deleterious mutation/epimutation-selection balance with and without inbreeding: a population (epi)genetics model.

Epigenetics in the form of DNA methylation and other processes is an established property of genotypes and a focus of empirical research. Yet, there remain fundamental gaps in the evolutionary theory of epigenetics. To support a comprehensive understanding of epigenetics, this paper investigates theoretically the combined effects of deleterious mutation and epimutation with and without inbreeding. Both spontaneous epimutation and paramutation are considered to cover a broader range of epigenetic phenomena. We find that inbreeding generally reduces the amount of segregating deleterious genetic and epigenetic variation at equilibrium, although interestingly inbreeding can also increase the amount of deleterious genetic or epigenetic variation. Furthermore, we also demonstrate that epimutation indirectly can cause increased or decreased deleterious genetic variation at equilibrium relative to classic expectations, which is particularly evident when paramutation is occurring. With the addition of deleterious epimutation, there may be significantly increased purging of deleterious variation in more inbred populations and a significantly increased amount of segregating deleterious variation in more outbred populations, with notable exceptions.

Can Neoliberal Capitalism Affect Human Evolution?

The connection between genes and health outcomes is significantly moderated by social factors. Health inequalities result from the differential accumulation of exposures and resource access rooted in class-based circumstances. In the neoliberal era in the United States, changed physical and socioeconomic conditions facing the poorer members of society have been characterized as traumatogenic (capable of producing a wound or injury). This paper will argue that research that points to the transgenerational influence of environmental impacts on health suggests 2 important reconsiderations of the link between the economy and health. First, an understanding of the health of any society requires an understanding not only of current but also past environmental conditions and the economy that produces those conditions. Second, it suggests that the way in which economic policy is analyzed needs to be reconsidered to incorporate the transgenerational impacts of environmental conditions produced by those policies.