r/BeAmazed • u/Acceptable-Elk3412 • 7d ago

Nature Cute

I don't know what I was expecting after she said, but they're also something else.

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u/781nnylasil 7d ago

This is all because of the DNA they inherited from their mom. She passed on more DNA from her black parent to the more black looking daughter and more DNA from her white parent to the white looking daughter. They both got 50% of their DNA from their mom but it’s not a guaranteed 25% from each grandparent.

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u/stuff_of_epics 7d ago

It’s not that it’s more or less, total. I suppose you could say ‘more’ if looking specifically at the genes that encode for darker skin. But the point is that it’s the actual gene(s) itself and not how many from either side; statistically, each grandparent accounts for 25%.

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u/AsperaRobigo 7d ago

This isn’t necessarily true. Statistically it’s most likely that it’ll be close to a 25-25-25-25 distribution, but when your body is making eggs or sperm, it doesn’t distinguish between DNA you got from your mother or your father. This is a phenomenon called random assortment.

Random assortment means a pair of eggs that formed from the same germ cell might be 80% one parent and 20% the other. If one of those eggs ends up fertilized, the resulting offspring’s DNA will be 50 percent identical to each of its parents, but in similarity to its grandparents will have a 10-40-25-25 split.

This isn’t necessarily common, since an even outcome is more statistically likely when things are random, but it’s not impossible for it to have happened in the case shown in the video.