In theory, if you have enough kids, would they start genetically repeating?


If you get 50% of dna from each parent, and there’s a finite amount of dna in each one, in theory, if you had enough kids (an impossibly large quantity) would your kids eventually be genetically identical to previous kids? Would the possible number of dna combination end eventually?

In: 20

You have 23 pairs of chromosomes. Each pair comes half from one parent and one from the other, so there’s four possibilities for each pair.

That would mean 4^23 or about 70 trillion possible combinations. The probability of having two kids with identical genes is so small it might as well be zero, unless they are identical twins.

There’s an incredibly varied but ultimately finite number of ways that meiosis can go to produce sperm/eggs in either parent, so it’s possible (in the absolute most theoretical sense) to produce one that is identical to a previous one.

If you manage to do that in both parents *and* then bring these two together as well, you could end up with a child that is identical to a previous one.

But in reality, this is never ever ever going to happen.

Well, if you had infinite kids, you would get infinite amount of exact duplicates of every single one.

Mathematically speaking, a finite number of definite objects can only be combined or selected from in a finite number of ways. This applies whether the discussion is genetics or pretty much a combination of anything.

But the combinations grow exponentially so anything past a fairly small number grows to an extent that it is for any (human) intents and purposes pretty much “infinite”. The simple example is shuffling a deck of cards. Only 52 cards but the number of different ways of arranging them is a number so large that if a different arrangement were made every second, it is likely that the time needed to do this would exceed the ultimate age of this universe.

Theoretically yes. But the number of kids you’d need to have before that became likely is not physically possible