Scientists at the Trinity College Dublin have successfully sequenced genomes of some of Ireland’s first settlers. And their study reveals that the Iris people got their pale skin and piercing blue eyes only in the Bronze Age. Findings of the study were published in the latest issue of Proceedings of the National Academy of Sciences (PNAS). Prior to Bronze Age, the Iris looked like people from the Middle-East or southern Europe, with black hair and dark eyes.

Scientists Sequence Genomes Of Ireland's Earliest Settlers

Technological achievements came to Ireland through migrations

Researchers sequenced genomes of a Neolithic woman farmer who lived near Belfast 5,200 years ago, and three men from the Bronze Age about 4,000 years ago. Sequencing genomes of ancient people could help researchers understand the history of Ireland. Scientists are keen to figure out whether technological achievements such as agriculture, use of stone and metal tools were local innovation or came through external migrations.

The study shows that technological changes came to Ireland through migrations. The farmer woman’s genome pointed to a Middle-Eastern ancestry. Agricultural was invented in the Middle-East. Lead researcher Dan Bradley of Trinity College Dublin said in a statement the Middle-Eastern people had physically moved with farming to the British Isles.

In contrast, genomes of the three Bronze Age men revealed a heavy genetic influence from the Pontic Steppe, a region in Eurasia around the Black Sea. It indicates that a large migration took place as culture moved from the stone age to the metal age. Notably, all the three men possessed genetic code for a disease called haemochromatosis or the inability to absorb iron.

Evidence of Celtic complexion goes back to 4,000 years ago

This disease is caused by a mutation of the C282Y gene, which also leads to piercing blue eyes. The mutation is so common in modern day Ireland that it is often referred to as the Celtic disease. These three men from the Bronze Age are the earliest evidence of Celtic disease. The degree of genetic change in them suggests the possibility of other related changes, such as the introduction of language ancestral to Celtic tongues.

Lara Cassidy, the co-author of the study, said genetic affinity was “strongest between the Bronze Age genomes and modern Iris, Scottish and Welsh.” It points to the establishment of key attributes of the insular Celtic genome about 4,000 years ago.