The ramifications of a new type of gene
economist.com
economist.com
And this immediately sets off alarm bells: Unfortunately experience shows that when researchers skip the “due process” of peer evaluation and go directly to the press they usually oversell their findings. I hope this isn’t the case here, and the findings hold up under scrutiny.
My own experience is that working with sperm RNA is a b*tch because of high stochastic noise. It’s basically impossible to get any clear signal from a whole-transcriptome assay. I’m therefore quite interested in their quantification.
And, finally, the effect on the offspring is completely unclear. One of the effects, which was reported here, is that offspring is less stressed (why? how? we don’t know; that’s a major missing puzzle piece). But systemic stress has quite a few, and partially drastic, effects — increasing expression of a particular microRNA is just one of many consequences. It also generally negatively affects semen quality (e.g. [1]), which doesn’t fare well for procreation.
And even just that particular microRNA in question, MiR-206, is tentatively implicated in multiple disease predispositions. You might make your children slightly less stressed. Or you might make it slightly more (or less) likely for them to acquire muscular dystrophy or schizophrenia.
According to the way the research was described, this mechanism acts outside of the genetic code, so it isn’t a matter of when sperm is produced. These particles can latch on to the gamete long after the gamete is produced. For example they can be present along the lining or interstitial fluids in the epididymis, where sperm passes through from the testes during reproduction.
But the RNA theory at least sounds possible to layperson.
And you’re right to be (in fact, this is exactly the same instinct researchers get). We’ll have to wait until the actual research article is published before we can assess the quality of their evidence. But in their defence, they performed a so-called functional verification by knocking out the suspect gene (MIR206) in mice and looking for phenotypic changes. It is relatively straightforward to perform this in such a way that you get statistically robust results. And it’s also straightforward to replicate independently, which will happen in due course.
However, the transport of micro RNAs on sperm is a pretty cool mechanism - hope it is correct!
Using microRNA virus to test the sperm transport mechanism seems to be a good idea. Glooging for "microRNA virus sperm transport" suggest the link: Intercellular Transport of MicroRNAs (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3580056/), This review brings into focus what is currently known and outstanding in a novel field of study with applicability to cardiovascular disease.
So, perhaps sperm transport of microRNA could be tested using some RNAvirus to produce cardiovascular desease.
Still, your fundamental idea has some merits. A more promising experiment would forego viral RNA and instead mutate the specific miRNA-206 in mice to carry a specific signature. Sequencing the resulting embryo in early development could show whether the mutated miRNA was taken up. I say “could” because there are fairly big caveat: miRNAs are short-lived (unless they are actively regenerated) and the concentrations may be too low to pick up a signal.
So, if you have unprotected sex with a women who recently was or will be impregnated by another man, you can still pass your microRNA and affect the child?