Yes, strained headline!
Environmental contamination can cause cancer and birth defects. Of particular concern are a group of toxic chemicals called endocrine-disrupters, which interfere with reproductive hormones and may cause sterility. A new study, published online this week in the Proceedings of the National Academy of Sciences, suggests that these chemicals can change reproductive behavior as well, and that these behavioral changes can be passed on from parents to offspring. If correct, these changes could alter the course of evolution by giving natural selection new targets to act on.
In 2005, a team led by reproductive biologist Michael Skinner of Washington State University in Pullman reported in Science that the fungicide vinclozolin, an endocrine-disrupter used to spray vineyards and other crops, causes fertility defects in the male offspring of female rats treated with the chemical. These defects are, in turn, passed down to the males of subsequent generations. The toxin did not appear to be altering gene sequences; instead, Skinner and colleagues found, vinclozolin was somehow causing other chemical groups to latch onto certain genes, changing their expression (Science, 3 June 2005, p. 1391). The phenomenon is known as epigenetic inheritance. Last year, Skinner’s group identified 15 epigenetically altered DNA sequences in the sperm of the vinclozolin-treated rats
More signs of intergenerational effects of low levels of endocrine disruptors. I had blogged recently about Bisphenol A having intergenerational effects (where exposure to a chemical agent causes consequences for offspring and off off spring, etc).
It’s still early, but remember Children of Men (good movie, see it).