HEIDELBERG, Germany, Feb. 15 (UPI) -- German scientists have narrowed the search for the tiny genetic differences separating humans from other primates to a specific collection of 22 genes.
Though the distinctions between humans and other primates are easy to see, the genetic differences are tiny. Researchers at the European Molecular Biology Laboratory in Heidelberg used a trick of evolution, the duplication of genes, to help narrow the search for those differences.
Duplicate copies of genes are created naturally. Duplicates may create problems, however, harming the survival chances of the individuals carrying them. In animals that do survive the genes likely mutate to harmless forms or to forms that create an advantage -- spurring species diversity. Tracking these changes back gives clues to the genetic heritage of a species.
The scientists found 22 genes, spanning about 10 percent of the human chromosome, that are duplicated in humans but not in other species. These are the most likely source of what makes humans distinctly human.
The findings are published in the journal Genome Research.
