WGS vs Genotyping: What's the Difference?
A buyer's guide to the two main types of DNA testing — and which is right for you.
If you're shopping for a DNA test, you've probably encountered two terms: whole genome sequencing (WGS) and genotyping. They sound similar — both analyze your DNA — but the difference in what they actually capture is enormous.
Here's the short version: WGS reads nearly 100% of your DNA. Genotyping samples about 0.02% of it. Everything else flows from that difference.
How genotyping works
Genotyping — the technology behind 23andMe, AncestryDNA, and MyHeritage — uses a microarray chip with hundreds of thousands of probes. Each probe checks a specific, predetermined position in your genome. If the chip has a probe for rs429358 (one of the APOE variants linked to Alzheimer's risk), it checks that position. If it doesn't have a probe for a rare variant you might carry, that variant goes undetected.
23andMe's chip checks roughly 700,000 positions. That sounds like a lot — and for common ancestry markers and a few hundred health conditions, it's sufficient. But your genome has 3 billion base pairs. The chip is checking 0.02% of them.
What genotyping is good for: ancestry composition, DNA relative matching, common trait reports, screening for a curated list of well-studied health variants.
What genotyping misses: rare variants, structural changes, copy number variations, and anything at a position the chip doesn't probe.
How WGS works
Whole genome sequencing reads every base pair — all 3 billion of them — multiple times (30x coverage means each position is read 30 times on average). Instead of checking predetermined positions, WGS captures the entire sequence and then analyzes it computationally.
This has profound implications:
- Rare variants that genotyping chips would miss are captured
- Structural variants (large deletions, duplications, rearrangements) are visible
- Your data remains useful as new research identifies new clinically relevant variants — no new sample needed
- You can re-analyze the same raw data with different tools for different purposes
Companies like Nebula Genomics and Dante Labs offer 30x WGS direct to consumers. Prices have dropped dramatically — from $1,000+ a few years ago to $299 today.
Cost comparison (2026)
| Test | Price | Coverage | Future-proof? |
|---|---|---|---|
| 23andMe (genotyping) | $99-$229 | ~0.02% | No — static snapshot |
| AncestryDNA (genotyping) | $99-$119 | ~0.02% | No — static snapshot |
| TellmeGen (genotyping) | $169-$249 | ~0.02% | No — static snapshot |
| Nebula Genomics (WGS) | $299-$999 | ~100% (30x) | Yes — reports auto-update |
| Dante Labs (WGS) | $299-$599 | ~100% (30x) | Yes — raw data reusable |
Which should you choose?
Choose genotyping if: you mainly want ancestry and a curated health overview at the lowest price. It's a good entry point — just understand its limitations.
Choose WGS if: you want comprehensive, future-proof genetic data. The price gap has narrowed to the point where $299 gets you 30x WGS — for many people, the extra $70-$200 over a genotyping test is worth the enormous increase in data quality and longevity.
Still unsure? Browse our directory of 28 DNA testing companies to compare all your options.