A recently released DNA map of Ireland reveals that people of Irish heritage have an increased vulnerability to certain complex genetic diseases.

Compared to people in the rest of Europe, Irish people have higher rates of cystic fibrosis, celiac disease, multiple sclerosis, and galactosemia, a metabolic disorder that prevents the breakdown of sugars in dairy, legumes and organ meats.

President John F. Kennedy, who was of Irish heritage, was believed to have had celiac disease.

Read More: John F. Kennedy very likely had celiac disease

According to National Geographic, the study, which was published in Scientific Reports, built on the People of the British Isles project, which previously looked at genetics in rural England, Scotland and Wales.

President John F. Kennedy, who was of Irish heritage, is believed to have had celiac disease.

President John F. Kennedy, who was of Irish heritage, is believed to have had celiac disease.

The ancestry DNA map, which also revealed that Irish people have more Viking DNA than was previously suspected, was pieced together by a team led by Gianpiero Cavalleri at the Royal College of Surgeons in Dublin. The researchers built the map after studying the genetics of over 500 Irish men and women.

The researchers found that in Ireland genetic signatures are clustered strongly with the four ancient kingdoms of Connacht, Leinster, Munster, and Ulster.

Read More: Irish people have far more Viking DNA than was suspected

According to the researchers, the ability to link genetic information to geographic origins will enable medical researchers to design studies that consider how and why a group of people may be affected by certain genetic diseases.

“It’s not good enough just to know you’re Irish; it could be useful for the researcher to know that your DNA has been influenced by a unique genetic subgroup from one part of Ulster,” researchers told National Geographic.

According to the Irish DNA map, Irish people have more Viking DNA than was previously suspected.

According to the Irish DNA map, Irish people have more Viking DNA than was previously suspected.

“Considering that something like 20 to 30 percent of North Americans can claim Irish ancestry, the new work affects plenty of people outside of the region. And if you need an organ transplant or skin graft, it could make a difference in how well your body accepts the tissue: The more genetically different you are from the donor, the shorter the life of the transplant—rejections are lower when the recipient’s genome and the donor’s have fewer differences.”

Read More: Massive genetic study reveals Irish have more Viking and Norman DNA than previously thought

The Irish DNA Atlas is an ongoing study and the researchers are still accepting donations of DNA. To participate, all eight of your great-grandparents have to have lived within about 30 miles of each other in Ireland, which the Genealogical Society of Ireland can help verify. For more information on how to participate in the study, visit FamilyHistory.ie.

Researchers have found that people of Irish heritage have higher rates of cystic fibrosis, celiac disease, and other diseases compared to other people in Europe.iStock