10ofRods
Verified Anthropologist
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Thank you so much for the answer. Just one question that is still unclear to me.
Here it says that 99.6% of DNA for all people on Earth is identical (National Institute of General Medical Sciences.)
So if they had a full DNA profile from the sheath why were investigators building the family tree to start with?
Because if you have someone's full DNA you just take his father's DNA and with 100% certainty you can say if that person is your father or not.
This is my question, will be so grateful if you can clarify it for me.
Because that remaining .04% or so is still thousands of data points, which define each individual on Earth (except identical siblings - but sometimes, even they have 1 or 2 unique variations).
We are 99.9% the same as chimpanzees.
95% or so the same as my little avatar companion.
And 60% the same as bananas. It takes me several lectures (about 4 weeks worth to explain just vertebrate evolution in these terms). We're possibly about 99.68 percent the same as Neanderthals (with whom we overlap and their genes form addition ways of marking individual heritage).
If you took DNA and stretched out the DNA in one human cell, it would reach to the moon and back 1500 times. There are 24,500 gene addresses in the human genome, and at each of those spots, we have 1-2 genes. That means we have about 2,400 unique gene addresses not in the chimp genome. WIthin those 2,400 uniquely human slots, we look for unique alleles (one of the genes involved in making hemoglobin has at least 500 variations; while we hear about there being only 2-3 eye colors, in fact there are many genes for brown (each different from the others) and quite a few for the reduction in melanin that causes blue - and so on. One's parents only have (at most) 2 of the alleles for hemoglobin each (and they pass on 1). The many individual probabilities are about 2400 to the 100th power at least. This is theoretically infinitely individual humans, because new alleles (it turns out in recent research) appear more often than we think.
In regards to those 480-500 alleles for the red pigment part of hemoglobin, some people in Britain share ancient alleles with a now-extinct species from Asia! Whereas, chimps and Neanderthal have minor variations that don't appear in us (for chimps, we diverged about 8 million years ago from a common ancestor - so big divergence in terms of the alleles themselves for chimps).
But we are really speaking of the gene map in general when we give such percentages. For many of the slots, all life has the same alleles (or very similar ones). Animals resemble animals more than they do plants; all animals are fairly similar; we mammals are just minor variations on theme.