Neanderthal Gene Analysis: Populations were Smaller, More Isolated

Though some studies have suggested that at least one-fifth of the Neanderthal genome can be found in human DNA, a recent study conducted by the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, shows that Neanderthal populations were typically smaller and more isolated.

Of course, the Neanderthals were once the closet relatives to modern humans, diverging somewhere between 550,000 and 765,000 years ago. These days, we can expect about 1.5 to 2.1 percent of our genetics to come from Neanderthal DNA, according to Live Science. However, this study's findings suggest that while Neanderthal's underwent genetic changes involving their skeletons, they saw much fewer adaptations involving behavior and pigmentation.

"One of the next goals was obviously to begin to explore the variation among Neanderthals," said lead study author Svante Paabo, an evolutionary geneticist at the institute, via Live Science

For the study, Paabo and colleagues analyzed three Neanderthal genomes from a 49,000-year-old specimen from Spain; a 44,000-year-old specimen from Croatia; and a 50,000-year-old specimen from Siberia.

Researchers specifically focused on 17,367 genes that encoded instructions for generating proteins. They concentrated on specific mutations that changed what amino acids went into the proteins, which could potentially alert their structure. Though these changes can have benefits, they are more likely to cause detrimental effects. In some cases, they may even accumulate in small, isolated genes that result in mutant DNA structures.

"We find that [Neanderthals] had even less [genetic] variation than present-day humans," Paabo said, via the news organization. 

Findings showed that Neanderthals were also more likely to carry a higher number of mutation copies than modern humans.

The comparison between the ancient Neanderthals further showed that modern human genes held a common link between heart and metabolic health, while Neanderthal ones did not.

Yet researchers caution that population growth may obscure the signal of certain gene differences. In other words, the researchers note via National Geographic that, "we need to figure out how much of today's pattern comes from ancient hunter-gatherers, and how much comes from our recent adaptation."

More information regarding the findings can be seen via the journal Proceedings of the National Academy of Sciences.