Can We Really Inherit #Trauma? - The New York Times
▻https://www.nytimes.com/2018/12/10/health/mind-epigenetics-genes.html
“These are, in fact, extraordinary claims, and they are being advanced on less than ordinary evidence,” said Kevin Mitchell, an associate professor of genetics and neurology at Trinity College, Dublin. “This is a malady in modern science: the more extraordinary and sensational and apparently revolutionary the claim, the lower the bar for the evidence on which it is based, when the opposite should be true.”
Investigators in the field say the critique is premature: the science is still young and feeling its way forward. Studies in mice, in particular, have been offered as evidence of such trauma-transmission, and as a model for studying the mechanisms. “The effects we’ve found have been small but remarkably consistent, and significant,” said Moshe Szyf, a professor of pharmacology at McGill University. “This is the way science works. It’s imperfect at first and gets stronger the more research you do.”
The debate centers on genetics and biology. Direct effects are one thing: when a pregnant woman drinks heavily, it can cause fetal alcohol syndrome. This happens because stress on a pregnant mother’s body is shared to some extent with the fetus, in this case interfering directly with the normal developmental program in utero.
But no one can explain exactly how, say, changes in brain cells caused by abuse could be communicated to fully formed sperm or egg cells before conception. And that’s just the first challenge. After conception, when sperm meets egg, a natural process of cleansing, or “rebooting,” occurs, stripping away most chemical marks on the genes. Finally, as the fertilized egg grows and develops, a symphony of genetic reshuffling occurs, as cells specialize into brain cells, skin cells, and the rest. How does a signature of trauma survive all of that?