The DNA Test Boom: Heart Disease Risk, Gene Accuracy, and the AHA’s Warnings
Despite 23andMe’s bankruptcy, at-home genetic testing is booming—but heart-related results remain controversial, with the American Heart Association urging caution.
Watan-Despite the recent bankruptcy of 23andMe, one of the most well-known DNA testing companies, the at-home genetic testing market is thriving and expected to grow to $7 billion over the next five years.
AHA Questions DNA Test Accuracy
Many companies now offer tests specifically targeting heart disease risk. However, the American Heart Association (AHA) has raised doubts about their accuracy and usefulness. In its April 8, 2025, statement in the journal Circulation, the AHA emphasized that results from consumer-directed genetic tests are not always conclusive and may have downsides.
According to Dr. Leland Hull, assistant professor at Harvard Medical School and lead author of the AHA statement:”These tests offer more equitable access to genetic information, but due to numerous limitations, results aren’t always definitive and can lead to potential negative outcomes.”
How the Tests Work
Consumers submit a saliva or cheek swab sample, which is then analyzed through one of two methods:
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Genotyping: A low-cost method that checks for known genetic variants—similar to skimming a book for typos.
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Sequencing: A full reading of every DNA base—like proofreading the entire book word-for-word.
Test accuracy varies based on the method, number of variants studied, and company standards.
Types of Genetic Tests for Heart Disease
The AHA classifies DNA tests for cardiovascular diseases into three types:
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Monogenic Disease Tests:
These rare, single-gene conditions include:-
Dyslipidemias: Extremely high LDL cholesterol levels
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Cardiomyopathies: Heart muscle diseases
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Thoracic Aortic Disease: Enlargement or rupture of the aorta
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Arrhythmic Disorders: Life-threatening irregular heartbeats
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Polygenic Disease Tests:
These assess risk for more common conditions like:-
Coronary artery disease
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High blood pressure
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Atrial fibrillation
Results are combined into a Polygenic Risk Score, ranking your genetic risk percentile—but not giving a direct probability of disease.
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Pharmacogenetic Tests:
These predict drug responses. For instance, about 30% of Americans don’t respond well to Clopidogrel (Plavix) due to the CYP2C19 gene variant, which increases the risk of blood clots after heart attacks.
Limitations and Racial Bias
Most genetic data come from individuals of European descent, which limits accuracy for people of other ancestries. This increases the likelihood of “uncertain significance” results among non-Europeans.
Confirming Results with Medical Testing
If a test detects a pathogenic variant, the AHA strongly recommends clinical confirmation via doctor-ordered tests. These may include cholesterol screening, stress testing, or heart imaging. A referral to a genetic counselor might follow, including family testing.
Lifestyle Still Matters Most
Even with genetic risk, diet, exercise, and lifestyle choices have a greater impact on heart disease. If you have a family history of heart problems before age 50, consult a doctor—insurance often covers clinically ordered genetic testing.
In conclusion, while the at-home DNA test industry booms, medical validation remains crucial—especially when dealing with complex conditions like cardiovascular disease.
