The secret about human evolution found in spit - the protein in our spit called MUC7 is encoded by a gene with a haplogroup that entered human populations through interbreeding with an archaic "ghost species" hominin population that predated Neanderthal or Denisovan prior to 150,000 years ago.

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The secret about human evolution found in spit - the protein in our spit called MUC7 is encoded by a gene with a haplogroup that entered human populations through interbreeding with an archaic "ghost species" hominin population that predated Neanderthal or Denisovan prior to 150,000 years ago.