Founder Effect - Franco American

Franco Americans, Familial Hypercholesterolemia and the Founder Effect

Large-scale research and genetic studies concur that familial hypercholesterolemia (FH) is a common genetic condition that impacts all races and ethnicities. In fact, it is estimated that 1 in 250 individuals worldwide have FH. That means, each of us reading this Family Heart Foundation blog probably knows someone who has FH. The number of people you know who may have FH may also increase depending on where you live and your ancestry, commonly referred to the “founder effect” in scientific publications.


A recent research paper highlights the impact of the familial hypercholesterolemia founder effect on Franco Americans, whose ancestors settled in the Northeastern United States including New Hampshire, Vermont and Maine from French Canada between 1840-1930. In short summary, due to mass migration of French Canadians to work in the mills of the Northeast, the tendency for the communities to stay together and produce offspring together, combined with the dominant inheritance pattern of FH, the prevalence of FH is much larger in present day Franco Americans – an estimated 2.4 million who live in the U.S. today.


From a genetics perspective, there are 11 distinct gene changes (mutations) in the LDLR gene in 90% of all French Canadian FH cases, with just 6 of these gene changes accounting for the vast majority of FH cases (85%).  These genetic FH changes are more severe than those found in the general population.

Founder Effect - Franco American

Are there other FH founder populations?

Yes. In addition to French Canadians, other FH founder populations include Ashkenazi Jews, Christian Lebanese, Finns, and South African Afrikaners.

If my ancestry includes an FH Founder population what should I do?

Whether your ancestry is from one of these groups or another, the most important thing to do if you have familial hypercholesterolemia, is reduce your risk of heart disease by managing your high cholesterol and other risk factors. Genetics tell one part of the story, but the most important point of your FH story is how you manage your condition.


In addition, raise awareness of FH in your community and with your family members. Since FH is inherited through families, it is important that all of your blood relatives are informed of their risk for having FH. In fact, each mother, father, brother, sister or child of someone who has FH, also has a 50% chance of having FH. And, as this research points out, some communities have a higher rate, or prevalence, of FH. Telling your friends, schools, church groups and other community members about FH and the importance of getting their cholesterol checked, could help someone else prevent heart disease.

How do I share information about FH with my family and community?

the Family Heart Foundation has many tools and resources for sharing information with your family and community which can be round on our Tools and Resources page.

How do I learn more about the founder effect in FH?

This research paper “Familial Hypercholesterolemia and the Founder Effect Among Franco-Americans: A Brief History and Call to Action” is available for free to read. the Family Heart Foundation is proud to report that the first author, Reed Mszar, was a summer intern and helped us analyze some of our CASCADE FH® Registry Data on Franco Americans. Dr Dervilla McCann, the senior author, is a former CASCADE FH® Registry principal investigator.

Leave a Reply