Newgrange: Neolithic Bloodlines

DNA has been used to confirm the existence of an elite social class in the Stone Age Ireland, similar to those found among the pharaohs of ancient Egypt and the "god-kings" of South America's Inca Empire. 

A key piece of evidence comes from an adult male buried at the 5,000-year-old Newgrange monument in Co. Meath, Ireland. The team headed up by Dr Lara Cassidy were able to extract DNA from the petrous bone of the ancient corpse, a dense part of the inner ear. Ancient DNA is only preserved well in the body's densest bones, making the petrous portion an ideal extraction point. 

By sampling the hard-rock bone using a grinder they were able to place the bone shavings in a solution that releases DNA from the bone; allowing them to sequence the entire ancient human genome. After sampling 44 whole genomes, they were able to reveal that the adult man's parents were first-degree relatives - brother and sister or parent and child. Evidence of incestuous unions like that found at Newgrange is rare in human history; they are taboo for interlinked biological and cultural reasons. Where they do occur, it is often within royal dynasties that have been granted divine status. Brother-sister or parent and child marriages paired with the construction of extravagant monuments are usually indicators of a royal lineage, similar to Tutankhamun's parents who are thought to have been full siblings. And with Newgrange being older than Stonehenge and the Pyramids of Giza, the fact the man's remains were laid in a richly decorated recess in the inner chamber, suggests he was one member of an expansive ‘clan' that were buried at impressive stone monuments across Ireland.