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There are a total of 324 million known variants from sequenced human genomes. https://en.m.wikipedia.org/wiki/Human_genetic_variation

Is there an DNA sequence that is true for all primates? Is this more acceptable on another site maybe?

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    $\begingroup$ It's not totally clear what you mean by the words "identifier" and "true". do you mean "is there a DNA sequence that exists in all primates?" if so, how long do you need it to be? does it need to be in a homologous location in all primate genomes? It is trivially true that the one-letter sequences A, G, C, and T exist in all primate genomes, but I doubt that is what you mean. why do you want this sequence? $\endgroup$ Mar 16 at 22:43
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    $\begingroup$ Please rephrase your question. It is not clear what is meant with "324 million variants from..". Is this the total number of human genomes that have been sequences or are these the total number of alleles that have been found? Please also report your source. Please also specify what you mean with "identifier". Do you mean any sequence, that is common in all human genomes, but is expected not to occur in any other species? Then the answer - forced by stochastics- is yes, without any doubt whatsoever. Finally, what does your last sentence mean? $\endgroup$
    – KaPy3141
    Mar 16 at 22:50
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Ribosomal RNA sequences (rRNA) are present and highly conserved in nearly all organisms (excluding viruses) and serve as the basis for reconstructing the tree of life (archaea, bacteria and eukaryota). Such reconstruction obviously implies that there also differences between rRNA sequences, but they are smaller for a limited taxonomic groupings, such as primates. Still, even within primates there is some variation, although identical regions can be identified, see, e.g., here.

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Thanks to your Wikipedia link, I was able to track what you meant with "324 M variants". These numbers refer to entries in the dbSNP (single nucleotide polymorphism database).

If you have a look at the submission guideline, it is not allowed to submit sequences over 50 nt: https://www.ncbi.nlm.nih.gov/snp/docs/submission/hts_launch_and_introductory_material/

This means your number doesn't necessarily refer to either the number of known alleles (might be longer) or the number of fully sequences humans (might give many SNPs per sequencing).

Anyways, if you compare this (incomplete) number to the size of the human genome (3.1 billion), you will see that the genome is roughly 10x bigger than the total count of known SNPs. Those heavily are enriched in SNP loci, meaning they overlap in location.

So from this data one may only say that >>90% of the genome consists of non-known SNP sites. So your question is answered with a yes, most of the genome is similar/"true", while this just reflects the current state of knowledge and most certainly, the number of known SNPs will increase over time.

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