Whole genome sequencing is becoming the standard of care in clinical genetics. Costs have dropped dramatically, diagnostic yield continues to outperform older testing methods, and the technology is now accessible to individuals — not just research institutions. But the volume of information available about WGS can be overwhelming.
This guide covers everything you need to know: what whole genome sequencing is, how it works, what it costs, what it can and cannot tell you, and how to evaluate providers.
What is whole genome sequencing?
Whole genome sequencing (WGS) is a laboratory process that determines the complete DNA sequence of an organism's genome — all 6.4 billion base pairs in the case of a human. Unlike targeted genetic tests that read pre-selected portions of DNA, WGS reads everything: every gene, every intron, every regulatory region, and every stretch of DNA between genes.
The output is a complete digital map of your DNA. At clinical-grade depth (30X coverage), every position in your genome is read an average of 30 times, ensuring 99.98% accuracy. A typical result identifies between 4.6 and 5 million genetic variants per individual.
How it works
The process involves four stages:
- Sample collection: A saliva sample collected at home using a kit sent to your address. No blood draw or clinic visit required.
- DNA extraction and sequencing: Your sample is processed in a certified laboratory where DNA is extracted and sequenced using next-generation sequencing technology.
- Bioinformatic analysis: Raw sequencing data is aligned to the human reference genome, variants are called (identified), and each variant is classified according to ACMG (American College of Medical Genetics) guidelines.
- Report generation: Clinically relevant findings are organized into physician-readable reports covering specific health categories — hereditary cancer, cardiovascular, neurological, pharmacogenomics, rare disease, and more.
What WGS can tell you
A comprehensive whole genome sequence can provide information across several clinical areas:
- Hereditary cancer risk: Variants in genes like BRCA1, BRCA2, TP53, and Lynch syndrome genes (MLH1, MSH2, MSH6, PMS2) that increase cancer predisposition.
- Cardiovascular risk: Genetic variants associated with conditions like familial hypercholesterolemia, cardiomyopathies, and arrhythmias.
- Pharmacogenomics: Variants that affect how your body metabolizes specific drugs — informing which medications are likely to work, which require dosage adjustment, and which should be avoided.
- Rare disease diagnosis: For patients on a "diagnostic odyssey," WGS can identify variants in genes that no targeted test was designed to check, with diagnostic yields of 25–50%.
- Carrier status: Whether you carry variants for recessive conditions (like cystic fibrosis or sickle cell disease) that could affect future children.
- Neurological conditions: Genetic factors associated with conditions like Alzheimer's disease, Parkinson's disease, and epilepsy.
What WGS cannot tell you
Whole genome sequencing is powerful, but it has important limitations:
- It does not diagnose conditions. It identifies genetic variants. Diagnosis requires clinical interpretation by a physician who considers your symptoms, medical history, and family history alongside genomic findings.
- Not all variants are understood. Approximately 50% of identified variants are classified as "variants of uncertain significance" (VUS) — meaning there isn't yet enough scientific evidence to determine their clinical impact.
- It doesn't measure gene expression. WGS shows what's in your DNA, not which genes are currently active. RNA sequencing (transcriptomics) addresses this separate question.
- Environmental factors aren't captured. Diet, lifestyle, exposure, and epigenetic changes all influence health outcomes and are not reflected in a DNA sequence.
What it costs in 2026
The cost of whole genome sequencing has dropped from approximately $100 million in 2001 to under $500 for clinical-grade 30X sequencing in 2026. This price includes sequencing, bioinformatic analysis, and clinical reporting.
At Dante Labs, the Genome Test includes 200+ clinical reports delivered through the Genome Manager platform, with lifetime report updates as science advances.
It's worth noting that WGS is increasingly covered or partially covered by health plans in certain clinical scenarios — particularly for rare disease diagnosis and hereditary cancer screening. Check with your provider for current coverage policies.
How to evaluate a WGS provider
Not all whole genome sequencing services are equivalent. When evaluating providers, consider:
- Sequencing depth: Clinical-grade WGS requires a minimum of 30X coverage. Lower coverage reduces accuracy and variant detection.
- Laboratory accreditation: Look for CLIA certification, CAP accreditation, or ISO 15189 medical laboratory accreditation — the standards used for clinical diagnostic testing.
- Report quality: Reports should be physician-readable, use ACMG variant classification, and cover multiple clinical areas — not just ancestry or traits.
- Data protection: Understand where your data is processed (jurisdiction matters), whether the provider sells data to third parties, and whether you can request permanent deletion.
- Report updates: Because genome science advances every year, check whether the provider offers automatic reanalysis and report updates as new variant-disease associations are validated.
- Raw data access: You should be able to download your complete raw data (FASTQ/BAM/VCF files) at any time.
Who should consider whole genome sequencing?
WGS is relevant for a wide range of people:
- People with a family history of cancer, heart disease, neurological conditions, or other heritable diseases who want to understand their own risk.
- Patients on a diagnostic odyssey who have been unable to get a diagnosis through conventional testing.
- People whose treatment isn't working — pharmacogenomic insights can explain why and inform alternatives.
- Proactive individuals who want the most complete picture of their genetic health, before symptoms or diagnoses force the question.
- People who have already taken a consumer DNA test and want to upgrade to clinical-grade, comprehensive sequencing.
Getting started
The process is simple: order a kit, collect a saliva sample at home, send it back with the pre-paid return label, and access your results through the Genome Manager in 6–8 weeks. No clinic visit or physician referral is required.
Once your genome is sequenced, your data is permanent. Your reports update automatically as science advances. And your complete genetic record is available to you — and any physician you choose to share it with — for life.