But that's not what it says. RNA fragments are entering the ovum and having some sort of effect .... that's quite different from passing traits the way genes on chromosomes do.

s/egg/which/

I and others generally don't quote things that aren't relevant to the point we're making and I'm not keen on the crypt-accusation. I didn't say that there aren't downstream molecular effects--clearly there are. Rather, the article is very unclear about the nature of epigenetics, and the wording about "transmitting traits" is misleading at best and leads to many unwarranted conclusions, as evidenced in the comments here. The statements I quoted are not about transmitting traits. e.g., "paternal exercise" refers to a trait of exercising, taking time to exercise, being motivated to exercise, etc. The "conferred benefit" of "enhanced endurance and metabolic health" is a different trait. If that is the trait being transmitted then that should be the trait being identified in male parents, not "exercise". Similarly, being exposed to nicotine is not the trait of having livers that are good at "disarming" nicotine, cocaine, and a host of other toxins ... and this is an extraordinary claim that requires extraordinary evidence, and the article provides one citation, from 2017.

And as an epigeneticist says in the article, we have no idea how RNA is having the effects its having.

As I said, I'm happy to wait until we have moved beyond this early stage of research before making any radical inferences.

>I also feel that this could maybe contradict what we learned from evolution theory.

It doesn't, but the article doesn't go into this detail, so people unfamiliar with the field wouldn't understand why. The keyword is epigenetics. I.e. how certain genes become activated or deactivated through behaviour and/or environmental influences. But the DNA sequence itself remains unaltered. So no evolution necessary. There are basically a bunch of molecules than sit on top of your DNA that regulate gene expression. They don't just tell a cell to behave like a skin cell or a brain cell, they also regulate the entire cellular metabolism. The discovery that male sperm can also transmit this epigenetic information to offspring is relatively new, but now that we know that, it makes total sense that these gene-expression-modifying behaviours in fathers could affect their children. After all, they simply get to start with a good (or bad) bunch of epigenetic markers. They will not persist across many generations though, so it has no real long term effect on evolution. It may even be an evolved mechanism that allows organisms to respond to environmental changes on timeframes that would be prohibited by evolution.

Speaking mostly from personal experience here, if a kid gets a suped-up liver from their dad's smoking habits, cool. But how many kids fathers stopped smoking when the kid was born? My point, the father's smoking habits may have passed down a strong liver but his continued use damaged the child's lungs and possibly more.

These mechanisms of epigenetic inheritance or whatever need much more study. It is far too early to draw any conclusions other than we need to keep researching.

If true, I suppose there is also a opportunity cost involved. Meaning selecting for better coping with nicotine, does not help selecting for smarter offspring and maybe even preventing that. So it might be somewhat positive but at a cost unknown.

Also there are the very known costs of nicotine damaging sperms, or of course being in literal smoke as a child (or adult) and deal with those real effects.

  >Think of all the kids of the 60th and 70th. They must be immune to most toxins ;).

But seriously though, "immune" is a humorous exaggeration, but I'm not sure we have data to rule out the idea that this cohort has increased tolerance to some environmental toxins.

So it's possible the level of harm we see today is already "post-" this protective effect, if any.

> They must be immune to most toxins ;)

Allergies and cancer are way up.

There’s multiple causes behind those, this is almost certainly one.

For an example, scientists discovered both viruses and genetics long before they knew the molecular basis of either of them.

I'm well aware of that. The point is that people are drawing all sorts of unwarranted conclusions from this lay report on early stage research.

the only purpose of hacker news comments is to aggravate readers with overly reductive takes

For this particular research, it's possible as only 5% of mouse experiments become available to humans.

But a lot of life-saving medicaments and techniques started as mouse testings, including Penicillin, cancer drugs and the polio vaccine.

> You took a left-turn

I certainly didn't; I simply quoted a sentence from the article. (I've noticed that some people have difficulty distinguishing between the person who quotes something and the person being quoted ... it might be a Sally-Anne effect.)

> It’s the rest of the crap in smokes and vapes to be concerned with.

Yes, which makes this article even less reliable.

nicotine is significantly more harmful than caffeine, although it is definitely way better than the other stuff in tobacco and not a carcinogen.

let’s not get started on the CFS stuff, treatments for functional disorders are often placebo-resembling.