Whole-genome sequencing vs. consumer DNA tests, explained

Two different technologies

23andMe, AncestryDNA, and MyHeritage all use genotyping arrays: a chip that reads a fixed set of hundreds of thousands of specific, already-known positions in your DNA. Whole-genome sequencing (WGS) and whole-exome sequencing (WES) work differently — they read your DNA directly, base by base, across a much larger share of the genome (WES focuses on the protein-coding regions; WGS covers substantially more of the genome beyond that). Sequencing typically produces a VCF file rather than the raw text export a genotyping array gives you.

Why the difference matters

A genotyping array can only report on the positions it was built to read. If a genetic variant relevant to a health finding sits outside that fixed set, an array simply has no data there — it’s not that the finding is negative, it’s that the position was never read. Sequencing-based files typically cover more of the genome directly, so they can in principle support findings an array-based file cannot.

Who sells whole-genome sequencing today

If you have never tested and want sequencing rather than a genotyping array, a few companies sell it directly: Mito Health offers whole-genome sequencing at 30x clinical-grade depth alongside a broader menu of lab panels on a membership model, and Nucleus Genomics sells a $499 whole-genome test screening for 2,000+ conditions, including a dedicated family-planning product for carrier screening ahead of having children. Both require a new sample and a new purchase. DNA Layer is built for a different starting point — the raw data file from a genotyping-array test you have already taken — which is why it costs less and needs no new sample, at the cost of not (yet) reading the wider variant set a whole-genome sequence covers.

If you have a WGS or WES (VCF) file

DNA Layer today reads raw data exports from 23andMe, AncestryDNA, and MyHeritage. Support for whole-genome and whole-exome sequencing (VCF) files is on our roadmap but not live yet — if you upload a VCF file now it will not be accepted. Join the list above and we will let you know as soon as VCF support ships.