Evolutionary consequences of epigenetic inheritance
05 July 2018
In recent years, the belief that the genetic code is the sole basis for biological inheritance has been challenged by the discovery of trans-generational epigenetic inheritance. Environmentally induced phenotypes can in this way persist for several generations, due to the transmission of molecular factors that determine how DNA is read and expressed. Epigenetic regulation of gene expression is a common process that acts during the differentiation of somatic cells, as well as in response to environmental cues and stresses, and the passing on of these modulations to the offspring constitutes epigenetic inheritance.
Epigenetics and epigenetic inheritance can have profound influence on evolution. Trans-generational epigenetic inheritance not only needs to be taken into account when estimating quantitative genetic parameters, but it can also respond to selection and influence adaptation to new environments. Thus, the emerging field of epigenetic inheritance has many similarities with the now well-developed field of phenotypic plasticity, which has moved from being considered a nuisance, into becoming a major research field with considerable importance for adaptation. Plasticity and epigenetic inheritance can share underlying mechanisms that regulate gene expression. In both cases the degree of environmental heterogeneity and its stability over generations emerges as a determining factor influencing their evolution.
Epigenetic inheritance, includes DNA methylation, histone modification, and small RNA transmission.
DNA can't explain all inherited biological traits, research shows
They introduced changes to a histone protein, mimicking those that occur naturally, causing it to switch off nearby genes. The effect was inherited by subsequent generations of yeast cells.