Genetic memory: accessing the past through our DNA
Contributed by Poyin Chen
The premise for the video game, Assassin’s Creed, is based on the technological ability to re-live our ancestors’ experiences by accessing their memories inherited through their DNA. While this is actually scientifically impossible, the concept of heritable “memories” through epigenetic programming is currently an active area of study.
A publication by Fang et. al. studies the transgenerational effect of in utero caffeine exposure in the cardiac tissue male mice. Embryonic development is marked by a rapid demethylation event, followed by a re-methylation event. This demethylation event serves to remove any epigenetic imprints that the parental DNA possessed, however, this event can be influenced by many factors, one of which being nutrition.
Caffeine exposure in utero is known to result in low birth weight in F1 progeny but Fang et. al. sought to explore the effects of this exposure on F2 and F3 progeny who are not directly exposed to caffeine at any point in development.
The study found that depending on the stage of embryonic development at which caffeine is introduced, F1 progeny would have differential cardiac phenotype and function as well as differential expression of genes involved in cardiac development. In addition, exposure of F1 embryos to caffeine resulted in a significant change in cardiac phenotype and function in F2 and F3 progeny.
While we may not be able to relive our ancestors’ memories as extensively as this video game portrays, in the future, we may be able to genetically identify how our parents’ actions (such as ingesting too much caffeine) shaped who we are today.
Reference: Fang X, Poulsen RR, Rivkees SA, Wendler CC. In utero caffeine exposure induces transgenerational effects on the adult heart.2016 Scientific Reports.