WARNING: Potential spoilers ahead for those who aren’t up to date on Game of Thrones, and best take the mathematics used in this investigation with a few massive grains of salt.
Ever since Jon Snow and Daenerys Targaryen hooked up at the end of season seven on Game of Thrones, everyone who is even slightly emotionally invested in the show had only one reaction: That’s just disgusting and I don’t care how good looking they are.
For those who are unaware, Jon Snow’s actual parents are Lyanna Stark (Ned’s sister) and Rhaegar Targaryen, who is Daenerys’ older brother, making Jon and Daenerys blood-related relatives. To be really specific, the couple are aunt and nephew.
You’re related! No, stahp!
Now incest isn’t exactly a new thing on Game of Thrones but Jon and Daenerys’, uh, family reunion does bring up a very interesting question that just randomly came up amongst the GOAT team: what are the chances that aunt and nephew will produce another evil monster like Joffrey?
First things first, we have to assume Daenerys can have children. I know that the witch lady from season one says she can’t but you don’t bring that fact back up in season seven without it meaning something or having it come back around so let’s just say she can for the purposes of this investigation.
We know that an incest baby will have a chance of being born with a birth defect due to our genetic make up. To put it very simply (courtesy of The Conversation), people have two copies of every gene and can get away with having one copy be faulty. But if two people with similar genetic material (say, an aunt and nephew) produce a baby, there’s a much higher risk of the little bub having both copies of their genes being faulty, thus resulting in birth defects.
Cousin-cousin couplings were pretty damn common back in the old Victorian eras and while these are obviously bad in incest terms, the actual risk of a child being born with a birth defect is “only” 4% to 7%. Now we’re not saying that this gives you the all clear to go after your cousin but the risk is lower than what you may have initially thought.
Now this risk increases the closer two people are genetically linked and using some numbers from an “inbreeding” study from 1971, we know that cousins share one eighth of their genes, parents and kids share half, identical twins share everything, and aunts and nephews share a quarter.
Using some simple napkin maths, it is about four times as risky for a parent and their kid to have a kid with genetic defects compared to cousins, meaning aunt and nephews are about two times as risky and putting the number in percentage terms at around 8% to 14%.
Huh, that number is still lower than I expected but again, not a free pass to go after your aunt and I don’t care if she looks like Marisa Tomei or Emilia Clarke.
“Worth the risk?” “No.”
Now all that is for making a healthy baby with no birth defects, but what about the Joffrey factor? Well here’s where we gotta make a bit of a stretch.
We know from the show that out of Cercei and Jaime’s offspring, Myrcella, Tommen, and Joffrey, only the latter caught the asshole bug, giving us a one in three chance of an incest baby turning out very poorly. With such a small sample size, the margin of error is a bit big (about +/- 56% and that’s being generous) but let’s run with it.
Assuming that this asshole bug is genetic defect, then our napkin math turns out a grand percentage range of about 3 to 5% (with a margin of error of +/- 56%) in regards to Jon and Daenerys making another Joffrey.
So folks, if you were worried about having to see another sadistic monster, rest assured that the chances are pretty damn low.
That feeling is mathematics and incest slapping you in the face.
Having answered that long-standing question about Joffrey 2.0, the possibility of it happening is slim to none regardless due to what’s happened on the show so far. With Jon having found out about Daenerys being his aunt in the latest episode, not to mention the upcoming battle against the Night King, it’s likely that the pair will be too busy to even think about getting freaky, not that is a guarantee they will bang again after finding out they’re related.
But then again, incest was a thing the Targaryens did so who the hell knows at this point.
If there was anything to be gained out of this long-winded investigation, it’s that the chances of Joffrey happening again is slim and banging your relos is a big no no, regardless of the lower-than-expected (relatively speaking) birth defect rate.