>>1432027510% of all people are mentally deficient, half of whom are outright psychos. Altogether, 40% of the USA White population is functionally illiterate, defined as "given each square foot of floor tile costs one dollar and given the geometry of your kitchen, calculate how many dollars you need to tile your kitchen floor," and this number jumps to 60% or more if you begin asking questions such as, "given your friend, explain how he would talk to his friend and ask his friend how many dollars his friend would need to spend to tile his kitchen floor," which is of course the same question when your friend = you but this time expressed recursively.
A 10% chance is utterly insignificant.
For example, consider if your child was lactose intolerant. Then, feed it kefir. Kefir eats lactose, the output of which is milk without lactose but with other stuff (whatever it is kefir makes from starch, basically protein). Your ancestors are only 8njured if their intellect decreases to the point they lose kefir-making, which is nearly impossible - in which case, you should welcome certain dysgenics as it guarantees the extinction of those descendants of yours too stupid to manufacture fermented goods, too stupid to maintain redundant ferments in case one of two go bad (like a hard drive raid array), too sociopathic to be able to reply on their fellow race neighbors for aid or be friends themselves, and so on. In a strange way, celiac disease is eugenic as a dysgenic retarder.
Remember that your notions of eugenics hail not from Francis Galton but from a bunch of rich inbred idiots who mindlessly echoed galton's musings.