"JoAnne65;c-17038535" wrote:
"annaliese39;c-17038178" wrote:
"king_of_simcity7;c-17038036" wrote:
Queen Victoria married her cousin Albert and they have a lot of surviving children.
A good example of why a lack of genetic diversity can become problematic - in this case the spread of hemophilia amongst royals.
Hemophilia was passed through because both parents (cousins in this case) had it. That fact increased the odds. It’s estimated that 4 to 7 percent of children born to first cousins are likely to have birth defects, compared to 3 to 4 percent for children whose parents are more distantly related. That’s not nothing, but it’s also not the end of the world—or the family tree. Victoria and Albert had more children, grandchildren and great-grandchildren who had no hemophilia than those who did. The real issue would arise if the next generation of kids also married their first cousins. Their offspring will have even more DNA in common—and an even greater chance for birth defects. (source).
Apart from the fact a couple can also decide not to have children if they don’t want to take the extra risk. In any case, I seriously object against ‘ew’, because having a higher chance to have children with birth defects is not ew. It’s sad at most, for the persons who it concerns. Like a colleague of mine who is seriously epileptic and has to take heavy medicines that will guarantee (100%) birth defects, if she’d ever get children. She is married and not ew.
Oh no, of course! I don't think 'ew' when cousins marry (and certainly not when people with genetic defects or disabilities do either). I only meant to point out that in some cases there may be risks/difficulties for future generations over time if there is a lack of genetic diversity, such as when royal families insisted on maintaining the royal bloodline.
