What is Familial Hypercholesterolemia

Familial Hypercholesterolemia is a common genetic disorder characterized by dangerously high levels of low-density lipoprotein (LDL) cholesterol in the blood from birth, which significantly increases the risk of early-onset cardiovascular disease. Because the body cannot efficiently clear LDL cholesterol, it accumulates in the arteries, leading to plaque buildup long before it would occur in the general population.

What causes Familial Hypercholesterolemia?

Familial Hypercholesterolemia is caused by mutations in genes (most commonly the LDLR gene) that instruct the body to create receptors responsible for removing LDL cholesterol from the bloodstream. When these receptors are missing or defective, cholesterol levels remain persistently high. Unlike diet-induced high cholesterol, Familial Hypercholesterolemia is present from birth and does not respond solely to lifestyle changes.

How common is this condition?

While often classified as a rare disease, Familial Hypercholesterolemia is relatively common in a clinical context, affecting approximately 1 in 200 to 1 in 250 people worldwide. Because it is underdiagnosed, many individuals remain unaware of their condition until a cardiac event occurs.

What are the primary types and symptoms?

There are two main clinical classifications based on the inheritance pattern, which dictates the severity of the disease:

• Heterozygous Familial Hypercholesterolemia: Inherited from one parent; affects approximately 1 in 250 people.


• Homozygous Familial Hypercholesterolemia: A much rarer, severe form inherited from both parents; affects roughly 1 in 300,000 to 1 in 1,000,000 people.

What differentiates Familial Hypercholesterolemia from standard high cholesterol?

The defining feature of Familial Hypercholesterolemia is that it is a genetic, life-long condition. While standard high cholesterol is often influenced by diet and sedentary habits, Familial Hypercholesterolemia causes high LDL levels regardless of how healthy an individual’s lifestyle is. Physical signs can include xanthomas (cholesterol deposits under the skin) or corneal arcus (a white ring around the iris), which are rarely seen in non-genetic cases.

Next steps

• Consult a lipidologist or cardiologist to discuss screening and genetic testing.


• Request a full lipid panel and cascade screening for immediate family members.


• Connect with the 14 community members at DiseaseMaps.org who are navigating life with this diagnosis.

Medical disclaimer: This content is for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment.

References

• NIH Genetic and Rare Diseases Information Center (GARD)


• Orphanet (ORPHA:415)


• OMIM (Online Mendelian Inheritance in Man) entry #143890


• The FH Foundation (thefhfoundation.org)