The Trouble with Epigenetics, Part 3 – over-fitting the noise

The idea of transgenerational epigenetic
inheritance of acquired behaviors is in the news again, this time thanks to a
new paper in Nature Neuroscience (who seem to have a liking for this sort of
thing).
The paper is provocatively titled: “Implication of sperm RNAs in transgenerational inheritance of the effects of early trauma in mice”. The abstract claims that:
“We found that traumatic stress in early life altered mouse microRNA (miRNA) expression, and behavioral and metabolic responses in the progeny. Injection of sperm RNAs from traumatized males into fertilized wild-type oocytes reproduced the behavioral and metabolic alterations in the resulting offspring.”
Unfortunately, the paper provides no evidence to back up those extraordinary claims. It is, regrettably, a prime example of over-fitting the noise. That is, finding patterns in a mass of messy data, like faces in clouds, and building hypotheses on them after the fact. If any change in any parameter will do, it isn’t hard to fin…
The paper is provocatively titled: “Implication of sperm RNAs in transgenerational inheritance of the effects of early trauma in mice”. The abstract claims that:
“We found that traumatic stress in early life altered mouse microRNA (miRNA) expression, and behavioral and metabolic responses in the progeny. Injection of sperm RNAs from traumatized males into fertilized wild-type oocytes reproduced the behavioral and metabolic alterations in the resulting offspring.”
Unfortunately, the paper provides no evidence to back up those extraordinary claims. It is, regrettably, a prime example of over-fitting the noise. That is, finding patterns in a mass of messy data, like faces in clouds, and building hypotheses on them after the fact. If any change in any parameter will do, it isn’t hard to fin…