How long do epigenetic changes last?
Just how long these epigenetic effects last is not completely known. Other recent studies have also shown the power of environment over gene expression. For instance, fruit flies exposed to a drug called geldanamycin show unusual outgrowths on their eyes that can last through at least 13 generations of offspring even though no change in DNA has occurred (and generations 2 through 13 were not directly exposed to the drug). In another study, roundworms fed with a particular type of bacteria exhibit loss of a green fluorescent protein and a small dumpy appearance that lasts 40 generations. In human terms, factoring for 40 years equaling one generation, would represent 1600 years of generational history. Behavior also alters the epigenome But if nutrition or the lack thereof can apply biological stress that influences future generations, what about stressful emotional events? Michael Meany at McGill University in Montreal, Canada, found that newborn mice that were neglected by their mother
