London, July 1: Even small dosage of hormone intake can alter gene expression in a way that also affects the next generation, warns a study. In an experiment with pigs, the researchers demonstrated that the administration of even extremely low doses of an endocrine disruptor chemical (EDC) — an exogenous substance that has the same or similar effects as endogenous hormone — leads to epigenetic changes in a pregnant sow’s DNA.
These changes were also observed in the sows’ embryos, and similar changes were even evident after the offspring had reached adulthood, according to the study published in the journal Scientific Reports. Pigs’ hormonal changes during pregnancy closely resemble those in humans, so the results of the study are highly applicable to humans, she said. The researchers exposed pregnant sows to varying doses of estradiol-17-beta, a natural estrogen, via their daily feed either over the course of the whole gestation period or only during the first ten days after fertilisation.
The lowest dose corresponded to the acceptable daily intake for humans — 0.05 micrograms per kilogram body weight. The research revealed that estradiol affected the tissue-specific expression of about two dozen of the the 57 estrogen-related genes tested, according to dosage. (IANS)