>>14268719> a few of which correlate with race.No. Consider 2 populations “A” and “B”. Each population has 3 genes: G1, G2 andG3.
These populations only have one copy of the genes in their DNA – (haploid)
These genes come in two “types” : a “+” or “-“
Each individual in populations A or B has either a G1+ or G1-, a G2+ or G2- and a G3+ or G3- gene.
From sampling DNA in A and B we know 80 % of population A has the G1+ , G2+ and G3+ genes and 20% of population B has G1+, G2+ and G3+ genes.
You are given a DNA sample from a specimen from one of these populations ( you don’t know which), and are asked to determine which population the DNA comes from.
You find that gene G1+ present in the DNA sample. You could reasonably conclude that there is a 80% chance your specimen was from population A and a 20% chance the individual was from population B. Not exactly conclusive.
Looking at genes G2 and G3 , these both turn out to be G2+ and G3+ . The odds are now in your favor that this individual was from population A.
It turns out statistically, that if you only looked at one gene in this example, you have an 80% chance of classifying your specimen into the correct population. By looking at 3 different genes, the odds have now increased to 90% that you are correct. If you had had a hundred different genes to choose from, it would be almost impossible to make a classification error.
It turns out that you only need a few thousand genes to completely and 100% accurately classify a person into a race. In most cases, a few hundred samples will more than adequately do. All that is required for this to work is that the gene “concentrations” or frequencies are different between races. They are.
This is the point: its not that humans don’t share a lot of similar DNA, we do ; but we don’t share it equally. For genetic traits that rely on thousands of genes, the genetic differences between the races are staggering.
