Researchers have made a startling discovery looking at the DNA sequences of human remains found in Ireland, that were dated about 1,000 years apart.  The information indicates there was a sudden influx of people moving into Ireland between 5,000 and 4,000 years ago that markedly changed the make up of the Irish population, but they don’t know why.

An article in the Chicago Tribune says geneticists from Trinity College Dublin and archaeologists from Queen’s University Belfast sequenced the genomes of four ancient people from Ireland, and they were surprised at the differences they found.

Study author Dan Bradley. professor of population genetics at Trinity College Dublin said the team had been allowed to produce the genomes due to advances in technological and methodological procedures for DNA analysis.

The research team looked at four skeletons found in Ireland, one was a woman found in Belfast in 1855 and who lived over 5,000 years ago, and the other three were males found off Rathlin Island in 2006, who died about 4,000 years ago.

The team did not expect to find significant differences in the genomes since they lived relatively close together in the span of time, but it turns out they were strikingly different.

The findings show the woman was more Middle-Eastern looking, with dark eyes and black hair, while the four males were described as blue-eyed Easterners.  The rapid transformation led the scientists to surmise there was likely a great migration of eastern people into Ireland during the period between the skeletons.

Bradley said the team was surprised to see several of the genetic elements that are typical of the modern Irish genome appearing in the Bronze Age specimens, adding, since the genomes are more like modern Irish, that data suggests the establishment of the genetics for these populations around 4,000 years ago.

The researchers suspect the males may have come from the Pontic Steppe, an area of Eastern Europe near the Black Sea in what is now the Ukraine.  But, they say, researchers will need to sequence a lot more genomes from skeletal remains to determine when and where the migration took place before anyone can understand what drove these people to re-settle in Ireland.