- Reviewed by Christopher P. Cannon, MD, Editor in Chief, Harvard Heart Letter; Editorial Advisory Board Member, Harvard Health Publishing
Among your more than 20,000 different genes, one provides instructions for a protein called PCSK9, which helps regulate levels of "bad" LDL cholesterol in your bloodstream. About one in 250 people has a variant in this gene that causes LDL cholesterol to skyrocket, sometimes to more than three times the optimal ceiling of 100 mg/dL. This genetic condition, called familial hypercholesterolemia, is the leading cause of premature heart attacks in America.
But other people have different PCSK9 gene variants that have the exact opposite effect. Their LDL cholesterol is extraordinarily low—and their risk of heart attack is also far below average. This discovery, made by Dallas Heart Study researchers in 2005, spurred industry scientists to develop drugs called PCSK9 inhibitors (see "How does PCSK9 affect your cholesterol level?").
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About the Author
Julie Corliss, Executive Editor, Harvard Heart Letter
About the Reviewer
Christopher P. Cannon, MD, Editor in Chief, Harvard Heart Letter; Editorial Advisory Board Member, Harvard Health Publishing
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