Although it is a common – but incorrect view – that people can hand down their traits with their DNA sequences unaffected by what happens to them during their lifetime, epigenetic changes caused by external or environmental factors can affect offspring.
Now, University of Haifa research has found that the effects of exposure of females to stress during adolescence are transmitted not only to children, but also to grandchildren. “Our studies suggest that there are processes, unrelated to maternal care, that can explain how information is transmitted from generation to generation,” said Dr. Inna Gaisler-Salomon. Carried out with her doctoral student Hiba Zaidan, in collaboration with Prof. Micah Leshem, the study has just appeared in the journal Psychoneuroendocrinology
In previous studies, they found that exposing rats to stress during adolescence, before they ever become pregnant, causes behavioral changes among their direct offspring when the latter reach adulthood. The team also found a gene (CRF1) related to stress that expresses itself differently in the brain of individual offspring from the moment they are born. According to the researchers, this finding suggests that it is not maternal care that affects variations involving stress in offspring.