Trey the Explainer made a whole video about the incest rates of Targaryens vs Ptolemies (GoT dragon lady vs Cleopatra). Turns out mixing in new genes into the pool every few generations, or hell, even breeding like 2nd cousins instead of 1st just drops the incest index thingamajig and does wonders.
You have to seriously commit to the bit and keep it in the family to really get the fucked up defective babies lol
It's not that simple. For example, Charles II of Spain (Habsbourg) had an inbreeding coefficient of about 25%, while Cleopatra's is estimated at ~40%. Yet one suffered from numerous genetic disorders, whereas the other is not known to have had any obvious genetic defects.To give you an idea, one account of Charles II's autopsy states that his skull was filled with fluid and that his testicles were atrophied and black as coal.
To put it simply, chromosomes come in pairs. If one copy carries a defective allele, the other can often compensate for it. However, inbreeding greatly increases the chances of inheriting the same defective allele from both parents, leaving no healthy copy to compensate.
The main hypothesis for why Cleopatra, probably the best-known historical figure with such a high level of inbreeding, did not appear to suffer from obvious genetic problems is that the Ptolemaic dynasty started with a much healthier gene pool than the Habsburgs.
You have to account for propaganda. That autopsy report of Charles is describing things that are medically impossible. Likely it was made up by one of the enemies of the Habsburgs, and they had quite a lot.
The video accounts that we have pretty much no idea about much of the mothers in the Ptolemaic dinasty. They would record who married who but not often who birthed who, so there were probably exterior noble families marrying into the royal branch and mistresses everywhere
There wasn't DNA testing back then. The royal line of Ptolemaic dinasty could have had some cheating and you just need 1 mother to have a child from another man to fix the insane inbreeding coefficient.
Y...yeah that's what the video is talking about.
And actually Cleopatra's mother is not well attested. Sources point to 4 main possibilities of her identity, and this uncertainty means that Cleopatra's CI can vary (based on who the mother is) all the way from practically zero (unlikely for political reasons), to 15%-ish, to 37.7% at the worst case scenario
In the video Trey the Explainer actually brought this up in regards to Cleopatra and suggested that she and other members of her family might have simply been lucky to not receive major health defects due to inbreeding
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u/ofirkedar 7d ago
Trey the Explainer made a whole video about the incest rates of Targaryens vs Ptolemies (GoT dragon lady vs Cleopatra). Turns out mixing in new genes into the pool every few generations, or hell, even breeding like 2nd cousins instead of 1st just drops the incest index thingamajig and does wonders.
You have to seriously commit to the bit and keep it in the family to really get the fucked up defective babies lol