Here:
“When a woman breaks up with a man, she usually wants every remnant of him removed from her life. A new study suggests that, try as she might, there may be one last piece of him that she’s stuck with for good: his DNA. A study from Australia has managed to prove that fly offspring are able to resemble a mother’s previous sexual partner, even when conceived with their father’s sperm.”
“Male microchimerism in the human female brain“.
“Male microchimerism was not infrequent in women without sons. Besides known pregnancies, other possible sources of male microchimerism include unrecognized spontaneous abortion, vanished male twin, an older brother transferred by the maternal circulation, or sexual intercourse.” [Emphasis in bold added.]
Another possible source of foreign DNA besides semen is saliva. Some exchange of saliva seems very likely between lovers, especially from “French kissing”:
Swallowing semen might also transfer DNA fragments. It has been claimed for some time that DNA in food can be transferred into tissues:
Dominant homosexual men sometimes crow that making another man swallow their semen marks him as their inferior forever. Scientifically, they may have a point.
Julian O'Dea 
Posted by katmandutu on May 12, 2015 at 6:59 am
One swallow does not a Summer make, Julian. 😛 ( I couldn’t resist saying that! )
Research has only been conducted on flies, not humans, so I am a bit sceptical.
I was reading comments about this article and a few struck a chord with me.
NaeturVindur
20-10-14, 07:36 PM
“I don;t think this effect much effect on human reproduction. First of all, just to repeat this, this finding was NOT based in DNA. The hypothesis is that various nutrients that a male receives in early life makes their way into his seminal fluid. These nutrients then make their way into the females eggs, providing those eggs with the same nutrients. The composition of these nutrients somehow influences the development of offspring, making the effect detectable.
I think the point being forgotten is that these are flies, and their life span ranges from 20-40 DAYS. The period of time between larval eating and reproduction is maybe a week. So basically, these nutrients have to hang around in the female ovum for a few days.
If a human female has sex with one man, then a day or two later has sex with another man, and a few weeks later discovers she’s pregnant, there’s going to be confusion over who the father is anyway. PLUS the nutrients available in the seminal fluid from either partner are still going to linger for a few days anyway, so it will only influence the development of the blastula. I sincerely doubt this find will have much if any bearing on our understanding of human reproduction.”
Yatagarasu
20-10-14, 03:21 AM
“Telostylinus angusticolli and Homo Sapiens spermatozoa are completely different in many ways (viability, size, genome size, amount of sperm per mL, and actual composition). The important thing is not the genetic material (as @Erlian mentioned ). The actual article never even mentions our species. To make conclusions about Human DNA residuals and how it affects future offspring we would need to test this in Humans (which probably isn’t happening anytime soon).”
I JUST find this study hard to swallow… 😀
Posted by Julian O'Dea on May 12, 2015 at 7:29 am
The first citation above seems to report the second citation inaccurately, but the third and fourth papers I cite look like they refer specifically to DNA. And the evidence for incorporation of ingested DNA into tissues, given in the fifth citation, seems good. More evidence for this is found here:
Click to access 546f45e80cf24af340c07f5f.pdf
Posted by Jim on May 12, 2015 at 8:33 pm
“I JUST find this study hard to swallow… :D”
Hardy, har, har….har, har. 😉
Interesting info Julian.
Posted by Gerry T. Neal on May 12, 2015 at 6:18 pm
What scientists are now discovering about flies has been believed to be true about horses by horse-breeders for millennia. That foals sometimes inherit characteristics that belong not to their dam or sire but to their dam’s previous mates, horse-breeders call “throwing back”. For about a century it has been believed that Mendelian genetics has disproved this possiblity and that what breeders had been observing for centuries was to be explained by the combination of recessive genes the traits of which had not appeared for several generations. If the Australian studies stand up under further scrutiny and research this will not be the first time that science, after having dismissed with certainty a long-held belief as debunked superstition, will be forced to retract and admit that what they had previously declared impossible, is both possible and actual.
Posted by APL on February 28, 2016 at 12:07 pm
Gerry T. Neil: “That foals sometimes inherit characteristics that belong not to their dam or sire but to their dam’s previous mates, horse-breeders call “throwing back”. ”
Given the relatively small gene pool of for example thoroughbred horses, ‘throwback’ isn’t a completely unreasonable explanation.
Posted by Amfortas on May 14, 2015 at 3:00 am
There are scientists and scientists. Let’s see it replicated in humans before we get all excited. And where are the satellite photos that are de rigeur for any scientific discovery 🙂
Posted by Julian O'Dea on May 14, 2015 at 3:36 am
Yes, as I conceded in a comment above, not only are the first and second reports I cite in flies only, but the science journalist has mistakenly referred to DNA. The results really imply a type of environmental effect mediated by seminal quality; but they are quite interesting nonetheless:
“Although the second male sired a large majority of offspring, offspring body size was influenced by the condition of the first male. This effect was not observed when females were exposed to the first male without mating, implicating semen-mediated effects rather than female differential allocation based on pre-mating assessment of male quality. Our results reveal a novel type of transgenerational effect with potential implications for the evolution of reproductive strategies.”
However the remaining citations I give do refer to DNA. There does not seem to be much doubt that foreign DNA can find its way into the cells of those exposed to it. Microchimaerism in women’s brains (of DNA from foetal Y chromosomes) seems to be a real thing, and there have been reports for some years now that ingested DNA can find its way into the tissues.
One possible source of male DNA in women’s tissues has been suggested to be sexual intercourse:
http://www.ncbi.nlm.nih.gov/m/pubmed/16084184/
http://www.ncbi.nlm.nih.gov/m/pubmed/15550532/?i=2&from=/16084184/related
Posted by Julian O'Dea on May 14, 2015 at 3:57 am
This may be relevant, since mononuclear cells have been reported to carry foreign male DNA in women, and sperm from sexual intercourse are involved in this report on the reaction of mononuclear cells to sperm in infertile women:
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0044172
“Sperm Cells Induce Distinct Cytokine Response in Peripheral Mononuclear Cells from Infertile Women with Serum Anti-Sperm Antibodies”
Posted by Julian O'Dea on July 24, 2015 at 4:07 am
Posted by Julian O'Dea on July 27, 2015 at 11:27 am
https://en.wikipedia.org/wiki/Pre-eclampsia
Immunological aspects involving partner’s semen.
Posted by Julian O'Dea on November 4, 2015 at 10:28 am
http://unlimitedzz.com/be-careful-who-you-sleep-with/