I don’t think mitochondrial DNA has any impact on hair color.
It’s interesting that one of the theories of aging has to do with a reduced ability of mitochondria to repair themselves, because their DNA degrades.
But cellular, nuclear DNA has much better repair tools. And in fact out of the couple hundred genomes needed for the mitochondria, only about 19 actually are in the mitochondria, the rest are already in the nucleus.
So the theory is that by using viral vectors, the DNA that is prone to breaking and resequencing could be copied into the nucleus.
It’ll take more than that for somebody to ever get to their four hundredth birthday.
But not much.
We know what aging is. And soon we will be able to prevent and even reverse it.
Ping to medical/dna related stuff.