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Arthur T Knackerbracket has found the following story:
Offspring may inherit legacy of their father's Toxoplasma infection
Studying mice infected with the common parasite Toxoplasma, the team discovered that sperm of infected fathers carried an altered 'epigenetic' signature which impacted the brains of resulting offspring. Molecules in the sperm called 'small RNA' appeared to influence the offspring's brain development and behaviour.
'Intergenerational inheritance' of similar epigenetic changes from men exposed to extreme trauma has been well documented. This latest research, published in Cell Reports, has raised the question of whether Toxoplasma infections – or even possibly other infections – in men before conception could impact the health of subsequent generations.
The research was led by Walter and Eliza Hall Institute researchers Dr Shiraz Tyebji and Associate Professor Chris Tonkin, in collaboration with Professor Anthony Hannan at the Florey Institute of Neuroscience and Mental Health.
[...] Associate Professor Tonkin said people could carry the dormant Toxoplasma parasite for decades, and that this had been associated with the appearance of symptoms of mental disorders such as schizophrenia and bipolar disorder.
"Toxoplasma infections have been shown to cause long-term epigenetic changes in a range of cells around our body. These are changes that do not alter the genetic sequence of DNA, but influence gene expression – that is, which genes are switched on or off," he said.
[...] "We discovered that Toxoplasma infection alters levels of DNA-like molecules, called small RNA, that are carried by sperm," he said. "These changes in small RNA levels affect gene expression, and so could potentially influence brain development and behaviour of offspring.
"We were stunned to see that even the next generation – the 'grandchildren' of the original infected male – displayed changes in their behaviour," Dr Tyebji said.
Journal Reference:
Shiraz Tyebji, Anthony J. Hannan, Christopher J. Tonkin. Pathogenic Infection in Male Mice Changes Sperm Small RNA Profiles and Transgenerationally Alters Offspring Behavior. Cell Reports, 2020; 31 (4): 107573 DOI: 10.1016/j.celrep.2020.107573
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(Score: 3, Informative) by HiThere on Thursday April 30 2020, @11:51PM
Sorry about that. You're wrong, but it's not the simple thing that news stories make it out to be.
In the first place, most serious mutations end up dead well before birth. So you never see them.
The largest number of mutations are "neutral drift", which isn't really quite neutral, but is pretty close. So you can only track those by gene sequencing or some such.
Epigenetic modifications were not part of the "new synthesis" back in the 1950's, but they've been known and accepted for decades. And they were first detected by noticing inter-generational physical changes, so that's not new either.
But do note that epigenetic changes are largely random. Not entirely, as there is sign that, e.g., the tendency to accumulate fat can be fostered by the parents having experienced famine. What this seems to imply is that the tendency towards a particular epigenetic change is also subject to Darwinian evolution. But to a much lesser degree, as epigenetic changes will fade over the generations.
What seems new here is linking the particular parasite (Toxoplasma) to the particular inherited epigenetic change.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.