Why does incest result in birth defects? - eviltoast

Just to be well and truly fuckin clear. I am not now nor have I ever been nor will I ever be contemplating shagging a family member.

  • wieson@feddit.de
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    9 months ago

    Recessive isn’t always bad. In fact, many (maybe all) genetic traits have a dominant and a recessive information.

    For example peas. Let’s say there is a gene for colour. The dominant variation of the colour gene carries the information “green”. Let’s call this gene c for colour. Then there is a recessive variation with the information yellow.

    We’ll write the dominant information as capital C and the recessive as lowercase c.

    Now there is a pea with the genetic information CC (one from each parent). That’s a green pea.

    Then there is one with Cc (father green, mother yellow). But you see the pea and it looks just like a green pea. Because the green gene C is dominant and the yellow c is recessive. You don’t know, that this is a mixed variety.

    If two seemingly green peas pollinate each other, but under the hood, they are Cc, then they might produce a cc yellow pea.

    For a lot of genetic information that’s not a problem, they are just different characteristics and not harmful.

    But if you have B = your blood coagulates normally, and b = your blood doesn’t thicken, you just bleed out and die when you have a paper cut…

    Then inheriting b from both of your parents is a terrible fate.

    This happened in the House of Saxe-Cobourg and other nobility in the 19th century.

    Edit: the last part is actually a bit more complicated, but the explanation of dominant and recessive still works.