
Homozygous FH
What is homozygous familial hypercholesterolemia?
There are two forms of familial hypercholesterolemia (FH):
- Heterozygous Familial Hypercholesterolemia (HeFH)
- Homozygous Familial Hypercholesterolemia (HoFH).
The most serious and rare form is HoFH. Individuals with HoFH typically have untreated LDL levels between 400 and 1000 mg/dL. That’s four to 10 times the normal level. If left untreated, people with HoFH can develop heart disease in their early teenage years, sometimes as early as two or three years of old.
While HeFH is common, HoFH is a rare disorder. It is estimated that HoFH is found in 1 in 300,000 people around the world.
This rare disease happens when someone inherits two FH genes, one from each parent.

How is HoFH diagnosed?
HoFH can be diagnosed with a blood test, a physical exam, and family history. Every form of FH looks different in every person, but there are some physical signs and symptoms of HoFH:
Family History
HoFH is a family disorder. A person who has HoFH has inherited two FH genes, one from each parent.
High Cholesterol
Individuals with HoFH have LDL cholesterol levels over 400 mg/dL, and often much higher at birth.
Xanthelasmas and Xanthomas
Xanthelasmas and xanthomas are cholesterol deposits that are found under the skin or around the eyes.
Corneal Arcus
Corneal Arcus is a half-circle or full-circle of gray, white, or yellow cholesterol deposits in the outer edge of the cornea.
HoFH is Severe
It is important to remember that HoFH is a serious and life-threatening medical condition. HoFH leads to progressive and early heart disease in both men and women, as well as children.
Cholesterol deposits in the arteries of the heart can cause heart attacks in people under the age of 10, sometimes as early as two or three years old!
That’s why, if you or your child are diagnosed with HoFH, one of the first steps to take – as soon as possible – is to seek expert care.


Find help getting the care you deserve
Navigating health care today can be frustrating and difficult. The Family Heart Foundation can help you navigate your journey FH. Experts at the Care Navigation Center are ready to answer all your questions.
Treating HoFH
There are multiple treatments for FH available today and several more in development.
Supporting HoFH Individuals
The Family Heart Foundation hosts an online support group for individuals and family members affected by HoFH.
Finding an FH Specialist
HoFH is a complicated, life-threatening medical condition that requires an FH specialist's care.