Inbreeding was a huge problem within European nobility.
That is why, I presume, that with modern knowledge about genetics, Royals are marrying out.
Well, it is happening in England now, and has happened in Norway.
The genetics of inbreeding are simple. If you win the lottery it can even enhance traits. Think the crazy Targaryans in Game of Thrones. Equally likely and more deadly is the chance of two defective recessive genes combining.
Some mention the muslim world. In many countries cousin marriage is the norm. AND, for generation through generation. WHich of course quadruples the chance of a bad gene match. This is a “hidden” secret in Europe, where newborns from say, Pakistan have a lot higher rate of birth defects.
Sad all together. Do not have sex with your cousin :P
Considering that hardly any of mine were female, that wasn’t an issue for me, and those that were female were older and already married to someone else anyways, so no problem.
Many horror stories of Habsburg inbreeding, including “Charles the Bewitched”. Keeping the power & the money in the family has a serious downside.
Pakis are said to be 70% inbred (products of cousin-marriage). Most muzzie nations are also highly inbred.
Combine that with a demonic “religion” and a steady diet of adrenalin-soaked halal meat (animals are fear crazed at the moment of slaughter under halal), and the violent outcomes number in the tens of millions.
IMHO, most people have enough sense in their heads not to have children with their cousins. Plus the other factor: Arranged Marriage, isn’t the way any more.
“Some mention the muslim world. In many countries cousin marriage is the norm.”
One result is a HUGE incidence of diabetes.
From the WSJ...
“Roughly one in five people has diabetes in the Persian Gulf region, according to doctors and the International Diabetes Federation, or IDF, and three countries—Kuwait, Saudi Arabia and Qatar—are in the top 10 nations globally for the highest prevalence of the disease. The other seven places are all taken by tiny islands in the Pacific Ocean, while Bahrain sits at position 12, the United Arab Emirates is 15 and Egypt is at 17.”