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BiPoLaRadiation t1_isgxrl6 wrote

Reply to comment by sunplaysbass in When it's said 99.9% of human DNA is the same in all humans, is this referring to only coding DNA or both coding and non-coding DNA combined? by PeanutSalsa

To be fair the percentage of genes that are different is probably a lot higher than 30 percent. The 30 percent is the number of base pair sequences that are similar between humans and bananas. So us and bananas both have a gene for a sodium pump or some other gene that is shared between most living things and on average the similarity between our average gene and their average gene (of the roughly 7000 genes that they compared in the original study) is about 40 (actual original number) percent (or less because they tested gene products and not base pairs so a lot of minor variability will still result in the same protein product).

If you were to compare on a gene by gene basis then probably none of our genes would be the exact same as a bananas. We and bananas also have multitudes of genes that are exclusive to us or them due to the structural differences and the long long evolutionary divergence.

So a 0.6% difference in genetic sequence between humans including not just base pairs of genes but also non coding sequences is actually really tiny. It's enough of a difference to do a lot but it's not as big of a difference as you are imagining.

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Sylvurphlame t1_isis7ih wrote

The way my biology professor explained it, assuming I recall correctly after decades, is that it takes most of the DNA just to make a functional life from of any sort of complexity. So the amount the separates species, or individuals within a species is relatively small. But important.

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