Short answer
Familial hypercholesterolemia, or FH, is an inherited condition that can cause very high LDL cholesterol and early coronary artery disease. Genetic testing can confirm a diagnosis, support family cascade screening, and sometimes clarify risk, but FH can also be diagnosed clinically from cholesterol levels and family history.
What testing can and cannot do
| Result | Possible meaning | Limit |
|---|---|---|
| Pathogenic FH variant | Supports inherited FH and targeted family testing. | Risk and treatment still depend on LDL level and full clinical context. |
| No variant found | No known tested FH variant was identified. | Does not always rule out inherited high LDL or polygenic risk. |
| Variant of uncertain significance | A genetic change was found but meaning is unclear. | Should not be treated like a confirmed disease-causing result. |
| Family cascade testing | Relatives can be checked for a known family variant or high LDL. | Relatives still need medical follow-up, not just a report. |
How negative results are interpreted
A negative FH genetic test lowers the chance that a known FH variant explains the pattern, but it does not erase a strong LDL history or family history. Some families have polygenic hypercholesterolemia or variants that are not captured by a given panel. The practical next step is still based on the cholesterol pattern and who in the family needs screening.
When follow-up matters more
Follow-up becomes more important when untreated LDL is very high, when there is a family history of early heart disease, when a child or sibling may need screening, or when the report suggests a variant of uncertain significance. In those settings, the result should sharpen family risk assessment rather than stand in for the whole clinical picture.
When family history changes the next step
Follow-up matters more when the LDL pattern is severe, when early heart disease runs in the family, or when a negative result does not fully explain inherited high cholesterol risk. Genetics counseling helps decide whether cascade testing, lipid specialist review, or a more clinical diagnosis should drive the next step.
Questions to ask
- Do my untreated LDL levels and family history already meet clinical FH criteria?
- Which genes were tested, and does the report explain limitations?
- Should first-degree relatives have cholesterol testing or targeted genetic testing?
- How does the result change LDL goals, medication intensity, or screening for early heart disease?
Related guides: lipid panel, ApoB and Lp(a) tests, genetic testing for hereditary heart disease, and direct-to-consumer genetic testing.
How Genetic Testing Is Done
Genetic testing is usually done with blood or saliva, and the lab workflow depends on whether the question is a targeted variant, a panel, or confirmation after a clinical finding. Genetics counseling can help clarify whether the next step is a new test, family testing, or a different clinical workup.
FAQ
What does FH genetic testing look for?
It looks for pathogenic variants that can explain inherited familial hypercholesterolemia. The goal is to identify a genetic cause for the LDL pattern and to guide family testing.
Does a negative FH test rule out inherited risk?
No. A negative result does not always rule out inherited high LDL risk or a clinical FH pattern, especially when the untreated cholesterol history is strong.
Why is family testing useful if a variant is found?
Targeted testing for the known family variant can help relatives find risk earlier and decide who needs lipid follow-up.
How does genetic testing differ from clinical criteria?
Clinical criteria use LDL levels, family history, and physical findings. Genetic testing looks for a known disease-causing variant. They answer related but not identical questions.
Should children be checked for FH?
Children in affected families may need lipid screening or targeted testing because early identification can change prevention and treatment timing.
Who should explain the result?
A clinician, lipid specialist, or genetic counselor can help combine the report with LDL levels, family history, and treatment decisions.