You've lived with a coin-flip question since childhood. It takes courage to ask for the answer — and the answer changes everything.
Huntington's disease testing through whole genome sequencing provides definitive CAG repeat status, enabling life planning, family testing, and access to emerging disease-modifying therapies.
Huntington's Disease
Huntington's disease is a progressive neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the HTT gene, which encodes the huntingtin protein. Approximately 2.7 per 100,000 people worldwide carry the mutation, with higher prevalence in populations of European descent (10.6–13.7 per 100,000). The disease is characterized by motor symptoms (chorea, dystonia, parkinsonism), progressive cognitive decline, and psychiatric manifestations (depression, irritability, psychosis). Inheritance is autosomal dominant with essentially complete penetrance for repeat expansions of 40 or more CAG repeats. The disease is uniformly progressive and fatal, with mean survival of 15–20 years from symptom onset.
Normal HTT alleles contain 10–26 CAG repeats; 27–35 repeats are classified as intermediate (meiotically unstable but not disease-causing); 36–39 repeats show reduced penetrance; ≥40 repeats are fully penetrant and cause disease. Age of onset has an inverse correlation with repeat length: mean age of onset is 35–44 years overall, but longer repeats produce earlier onset. Juvenile Huntington's disease (onset before age 20, typically with ≥60 repeats) accounts for 5–10% of cases. Paternal transmission is associated with greater repeat expansion due to meiotic instability during spermatogenesis, explaining why juvenile-onset disease is typically paternally inherited.
Huntington's predictive testing is one of the most consequential genetic tests in medicine — at ≥40 repeats, the result is fully penetrant and definitive. A positive test enables psychological preparation, life planning including financial and legal decisions, enrollment in disease-modifying clinical trials (antisense oligonucleotides targeting mutant HTT are in advanced stages), reproductive counseling with options like preimplantation genetic testing, and informed decision-making. A negative result provides definitive relief and eliminates the need for surveillance. At-risk family members can now be tested with appropriate genetic counseling support.
Standard CAG repeat assays are accurate, but Genome Test with specialized repeat analysis provides precise sizing and detects somatic variability.
Precise repeat sizing matters — especially in the critical ranges
Huntington's testing is nominally straightforward — a CAG repeat assay is well-established. However, standard short-read sequencing panels and some Genome Test pipelines may not accurately size CAG repeats, particularly in the intermediate and reduced-penetrance ranges where precise counts have enormous clinical implications. The difference between 35 repeats (no disease) and 40 repeats (certain disease) is decisive. Somatic mosaicism in repeat length across tissues is now recognized as clinically relevant but not captured by blood-based testing alone. Long-read Genome Test capability or specialized repeat analysis can provide precise repeat sizing, detect somatic instability, and identify modifier variants in other genes (DNA repair genes) that influence age of onset.
Knowing your status enables preventive clinical trials and life planning
A positive Huntington's test is definitive — at ≥40 repeats, disease is essentially certain. That definitiveness enables people to pursue previously unavailable options: enrollment in disease-modifying clinical trials (antisense oligonucleotides like tominersen are in advanced development), reproductive counseling with preimplantation genetic testing (PGT-M) to prevent transmission, financial and legal planning while cognitive function remains intact, and psychological preparation with appropriate support. A negative result provides definitive reassurance. Family members can be tested with confidence in the result.
Your full DNA (not just a part of it)
Traditional genetic testing looks at narrow sets of genes, missing most parts of your genome. We sequence your full genome — every gene and every region between genes.
Comprehensive insights and specialized reports
Easy to read and with answers you and your doctor can act on. Not a file to interpret — 200+ clinical reports, organized by category.
Your test becomes more valuable every year
Your DNA does not change, but genome science is accelerating. Every month, new variant-disease associations are discovered. We validate these findings and update your reports automatically. Your test becomes more valuable every year.
The results doctors bring to their hardest cases.
Forty years of uncertainty. One test.
A patient had spent decades in the UK healthcare system without a diagnosis. Dante data, accepted by NHS clinical teams at Queen Elizabeth University Hospital Glasgow, identified Noonan Syndrome and a RUNX1 leukemia-associated variant that had gone undetected. After 40 years, they finally had an answer.
A complete read delivers a complete picture.
A patient came to Dante to investigate periodic paralysis. Reading the complete genome identified a concurrent hereditary cardiac finding — Brugada syndrome — that their doctor confirmed with an ECG. The result also explained a family member's unresolved cardiac history. One test. Every answer in it.
Sequenced in 2019. The data worked in 2021.
Jennifer sequenced her genome with Dante two years before her breast cancer diagnosis. When treatment began, Dante's pharmacogenomics data showed her prescribed chemotherapy would cause serious adverse effects. Her doctor selected an alternative — and she started effective treatment from day one.
Every genetic question deserves a complete answer.
Whether you are searching for answers today or protecting your health for tomorrow, a complete read of your entire genome is the only place to start.
It runs in your family. Now you can know if it runs in your genes.
Your genome contains inherited variants associated with medical conditions like cardiac, cancer, and neurological. We read all of them — with the clinical depth to give the result meaning.
Learn more →When traditional lab tests say you're fine. And you know you're not.
Standard diagnostic tests check for a pre-selected set of answers. We sequence your full DNA — including parts that no test was designed to check. If the answer is in your genome, we will help you find it.
Learn more →Your diagnosis may be right. Your treatment plan may be incomplete.
Your genes determine which treatments are most likely to work — and which are not. We give your doctor the tools and insights to inform your treatment plan.
Learn more →You want to know before something forces the question.
Some people don't wait for a diagnosis or a family history to act. Whole genome sequencing gives you the complete genetic picture now — so you and your doctor can make informed decisions before anything becomes urgent.
Learn more →You already took a DNA test. Here's what it couldn't tell you.
Most consumer DNA tests read less than 0.1% of your genome. We read all of it.
Learn more →Clinical-grade results. Chosen by individuals, trusted by doctors for their most complex cases.
Dante Genome Test helped specialists at a UK national acute hospital in the identification of Noonan Syndrome and a rare leukemia-associated genetic variant that had gone undetected. That result changed the medical care of the patient.
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Common questions about whole genome sequencing.
What is the difference between whole genome sequencing and a targeted genetic test?
Targeted genetic tests — including standard hereditary cancer panels — read a pre-defined list of known variants in a specific set of genes. They are designed to find what they already know to look for. Whole genome sequencing reads your entire genome: all 6 billion base pairs, every gene, every region between genes. A Mayo Clinic study published in JAMA Oncology found that standard testing guidelines missed more than half of patients with inherited cancer mutations. Genome Test does not have a fixed list.
What will I receive when my results are ready?
Your Dante Genome delivers 200+ physician-ready reports organized by clinical category — hereditary cancer, cardiac conditions, rare diseases, pharmacogenomics, carrier status, and more. Reports are delivered to your secure Genome Manager and are formatted for direct clinical use. Your genome data is permanently retained and re-analyzed automatically as science advances.
What happens if a clinically significant variant is found?
If a pathogenic or likely-pathogenic variant is identified, it will be clearly flagged in your physician-ready report with clinical context, published evidence, and recommended next steps. We recommend sharing any clinically significant finding with your physician or a genetic counselor, who can guide decisions about surveillance, risk reduction, or cascade testing for family members.
How is this different from a consumer DNA test like 23andMe or AncestryDNA?
Consumer DNA tests use genotyping chips that read less than 0.1% of your genome — a tiny pre-selected set of common variants. They are optimized for ancestry and population-level traits, not clinical genetic findings. The Dante Genome Test sequences 100% of your genome at 30X coverage, the same standard used in clinical diagnostic settings. The two tests are not comparable in scope, methodology, or clinical utility.
How long does it take to get results, and how are they delivered?
Your collection kit ships within 48 hours of ordering. Once your sample arrives at our CLIA-certified laboratory, sequencing and analysis takes 6–8 weeks. Results are delivered securely to your Genome Manager, where you can access your reports, share them with your physician, and receive automatic updates as new findings are validated against your genome.
We work with patient advocacy groups worldwide.
Dante Labs works with patient advocacy groups of any size — for Huntington's Disease and other conditions, rare and common. We support groups in any country, including virtual patient advocacy groups.
We can provide customized reports, group discounts, and packages tailored for your members. Please reach out using the form and we'll be in touch within two business days.
- Custom genomic reports for your members
- Group discounts and tailored packages
- Any country — including virtual groups
- Rare and common conditions covered
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We’ll be in touch within 2 business days. To follow up directly: hello@dantelabs.com
One test.
A lifetime of answers.
One kit, sent to your home. Your entire genome sequenced at the clinical standard used for diagnostic decisions. 200+ physician-ready reports delivered to your Genome Manager in 6–8 weeks — permanent and updated as science advances.
Ships within 48 hours · Results in 6–8 weeks
