Is High Cholesterol Genetic? FH and Lp(a)

Often both. Food, weight, and activity move your numbers somewhat, and genes set the baseline. Genes raise cholesterol in three main patterns: familial hypercholesterolemia (FH, one powerful gene change), polygenic hypercholesterolemia (many small variants that add up), and high lipoprotein(a), a separate inherited particle that standard tests leave out.

Genes are the most likely reason. Your liver makes most of your blood cholesterol and controls how fast LDL clears, and some people inherit slower clearance. Healthy habits still help your heart in many ways, though your number may stay high.

Ask your care team to rule out other causes too, such as an underactive thyroid, kidney or liver conditions, and some medicines.

FH keeps LDL very high from birth. A change in a gene that controls LDL clearance causes it, most often LDLR, less often APOB or PCSK9. Estimates range from about 1 in 250 people (a 2017 meta-analysis of 2.5 million people) to 1 in 313 (a 2020 analysis of nearly 11 million). The CDC uses 1 in 311.

FH is autosomal dominant: one changed copy is enough, and a parent with FH has a 50% chance of passing it to each child. According to the CDC, without treatment, heart attacks occur in about 50% of men with FH by age 50 and 30% of women by age 60.

An LDL-C of 190 mg/dL or higher is called severe hypercholesterolemia and is a key clue to FH. US guidelines have recommended a statin for adults 20 to 75 at this level, without a risk calculator, since 2018.

About 7% of American adults have an LDL-C of 190 or higher, and about 1 in 14 people at that level have FH. In a large genetic study, people at that LDL without an FH gene had about 6 times the risk of coronary artery disease compared with people under 130, and those with both a very high LDL and an FH gene had about 22 times the risk.

Yes. About 70 to 90% of the difference in Lp(a) between people comes from genes. About 1 in 5 people have elevated levels, it changes very little over a lifetime, and diet and exercise do not meaningfully lower it.

The 2026 ACC/AHA guideline recommends measuring Lp(a) at least once in every adult. It treats 125 nmol/L (50 mg/dL) or higher as a risk-enhancing factor linked to about 1.4 times the risk, and 250 nmol/L (100 mg/dL) or higher to about double the risk.

No medicine is yet FDA-approved to lower Lp(a). In September 2026, the first large outcomes trial of pelacarsen missed its primary endpoint: it lowered Lp(a) without significantly reducing cardiovascular events.

Clues include an LDL of 190 or higher, high cholesterol that holds steady despite a healthy diet, a parent or sibling with very high cholesterol or early heart disease, and tendon deposits. Doctors can diagnose FH from LDL, family history, and physical signs, and a genetic test can confirm it and let relatives test for the exact change (cascade screening).

Genetic high cholesterol usually needs medicine on top of healthy habits, often a combination: a statin, ezetimibe, bempedoic acid, or PCSK9 inhibitors and inclisiran, which lower LDL by roughly 50 to 60%. Ask your clinician what fits you.