The unique and distinctive Hebridean gene pool could shed light on the causes of diseases such as stroke, diabetes, heart disease and cancer and, in time, potentially point to new treatments for the general population, researchers say.
The genetic make up of people from the islands – which previous research has shown to be different from the rest of Scotland – will allow researchers to investigate how variations in Hebridean DNA influence the health of locals and the advantages it may give them.
The Edinburgh University study - which is aiming to recruit 2,000 people - will not be limited to people living in the Inner or Outer Hebrides, but will also include people with Hebridean grandparents who live anywhere in the world.
Participants will be asked to complete an online questionnaire about their health and lifestyle and to return a saliva sample by post, which researchers will use for genetic analysis.
Volunteers who live in the UK can choose to receive specific genetic information from their saliva sample. This information, provided in collaboration with the NHS, could help prevent future disease.
The MRC-funded research builds on the work of the Viking Genes study, which has recruited over 8,000 volunteers with Orkney or Shetland ancestry.
Professor Jim Wilson, lead researcher and Chair of Human Genetics, said: “Expanding the Viking Genes study will allow us to explore the unique genetic heritage of the Inner and Outer Hebrides. We will explore how the distinct gene pools influence the risk of disease today and investigate the Norse, Scottish and Irish components of ancestry in the different Hebridean isles.”
The study also involves the University of Aberdeen and NHS Grampian Clinical Genetics doctors Professor Zosia Miedzybrodzka and Dr John Dean.
A previous study of the DNA of people living in Scotland also led by Professor Wilson revealed "extraordinary" and "unexpected" diversity across the country.
The Scotland's DNA project tested almost 1,000 Scots to determine the genetic roots of people in the country.
It discovered four new male lineages, which account for one in 10 Scottish men.
It also found that actor Tom Conti is related to Napoleon Bonaparte.
Scientists were able to pinpoint a participant's DNA marker, from which they tracked the person's history and lineage.
Conti and Napoleon both share the M34 marker, which is Saracen in origin.
The project found that Scotland has almost 100 different groups of male ancestry from across Europe and further afield and more than 150 different types of female DNA from Europe, Asia and Africa.
Scotland's DNA also found that more than 1% of all Scotsmen are direct descendants of the Berber and Tuareg tribesmen of the Sahara, a lineage which is around 5600 years old.
Royal Stewart DNA was confirmed in 15% of male participants with the Stewart surname. They are directly descended from the royal line of kings.
Scientists believe comedian and presenter Fred MacAuley's ancestors were slaves, sold at the great slave market in Dublin in the 9th Century, despite his name suggesting a Viking heritage.
MacAuley's slave ancestor was taken by ship to the Hebrides and had an affair with his owner's wife, intruding DNA into the MacAulay line.