Unlocking Your Genetic Code: What You Need to Know About Genetic Testing

Written by Dr Saneka Chakravarty, MD, FACC. Dr Chakravarty is a board-certified cardiovascular disease specialist focused on personalized preventive cardiovascular care.

A genetic test result is a starting point, not a verdict. Here's what the two main types can and can't tell you.

The Two Types of genetic testing

Polygenic Risk Scores (PRS) add up thousands of tiny genetic differences to estimate your risk for common conditions like heart disease or diabetes. A score in the 99th percentile means your genetic risk is higher than 99% of people , not a 99% chance of getting the disease. It's a probability, not a prediction. One caveat: most scores were built on people of European ancestry and are less accurate for other backgrounds.

Single-gene tests look for one specific disease-causing change, like BRCA1/BRCA2 for breast and ovarian cancer, or the genes behind familial high cholesterol (FH) and hypertrophic cardiomyopathy (HCM). When one is found, it can unlock real, targeted prevention.

"Mutation" vs. "Variant" - Why It Matters

The clearer word is variant, because not every change causes disease:

• Pathogenic variant - good evidence it's harmful. A meaningful positive.

• Benign variant - harmless. Everyone has many.

• Variant of uncertain significance (VUS) - found, but not yet classified. Neither good nor bad news, just an open question.

  
  

A true negative is reassuring. A VUS is not a green light. Don't confuse the two.

Two Quick Corrections Worth Knowing

HCM isn't diagnosed by a gene test. If you already have HCM, imaging and ECG make the diagnosis , a negative gene test doesn't cancel that. Genetic testing's real value here is for your relatives: once your variant is known, family members who didn't inherit it can often skip years of heart scans.

At-home tests don't check everything. Some at-home BRCA kits screen only a few specific variants, not the whole gene. A "negative" means those few spots were clear , not that no harmful variant exists. With a worrying family history, it's not the end of the story.

You Don't Need a Family History

Single-gene testing used to be reserved for people with strong family history. That's outdated, many carriers have no family history at all. Ancestry (for example, Ashkenazi Jewish ancestry and certain BRCA variants) and population screening increasingly support testing on their own.

Before You Test: GINA Has Gaps

GINA protects you from genetic discrimination in health insurance and employment, but not in life, disability, or long-term-care insurance (consider applying for those first). It also doesn't cover already-diagnosed conditions, the military/TRICARE/VA/IHS/federal employee health plans, or employers with fewer than 15 employees.

FAQ

High PRS - will I get the disease? No. It's elevated risk, not a diagnosis. Your habits and care still do enormous work.

At-home BRCA was negative - am I clear? Not necessarily. Most kits check only a few variants. With a family history, ask a clinician about full testing.

I have HCM - still need scans if my gene test is negative? Yes. Imaging and ECG drive HCM care, not genetics.

Should I only test if it runs in my family? No, many carriers have no family history.

Bottom Line

Genetic testing offers insight, not destiny. How you live and the care you get still shape the outcome. The right test depends on your history, ancestry, and goals.

At Preventiononly, we use genetic testing to sharpen personalized prevention, at your discretion, in the full context of your health. Learn more at www.preventiononly.com.

For general education only, not a substitute for personalized medical advice.

References

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