Looking only at genetic code, is it possible that there have ever been two genetically identical people who are not twins (or clones)? How many medically distinct human beings can their actually be?
I’m assuming that we’re only talking about biologically modern human beings. So the genes that make us human cannot be eligible for variation.
If we don’t include environmental factors and non-DNA genetic material, what is the actual number of genes that can vary from one person to another? Do we even understand the human genome well enough to make this kind of calculation?
I’m assuming from combinatorial math that it’s more humans than can ever exist through the course of the entire universe. But what is the actual number? If those genes are varied at random, how many people will it take before they say a 50% chance that two of them are identical? For example, it only takes 23 people to have a 50% chance that at least two of them have the same birthday.
Edit: I found an interesting article about the complications with trying to calculate this number. The number seems to be on the order of 10^(tens or hundreds of thousands)
That’s pretty interesting. I’ve done some genotyping before, and I’m guessing that they probably check a handful of distinctive genes, not the entire genome.
For example, if they checked 45 binary markers (e.g. positive or negative) that would get you into that ballpark (assuming that they are evenly distributed and not correlated). Of course, there are also markers that are not binary but can have many different variations other than positive and negative.
That’s actually really cool to know. She was fairly confident they use the SNP method (it’s a third party provider), and described it the way you did. Sounds like full genome is possible but she didn’t think it likely, your explanation would support that.
Also, I made a correction to the numbers…I was very wrong lol