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Choosing your depth

DNA array or whole genome, how deep to read.

Both read your DNA. They differ in how much of it. A DNA array reads about a million pre-selected, well-studied positions; whole-genome sequencing reads every base, about three billion. The areas you can explore are the same, and so is the hand-written interpretation. What changes is how much of your DNA there is to read, and what can be reached.

What does whole genome find that an array can't?

A DNA array reads only the common, pre-selected positions printed on its chip, about a million of your three billion bases. Whole-genome sequencing reads them all, so it reaches the rare and private variants, the finer structural changes, and the fuller medicine-handling detail an array never reads.

The honest difference

What an array reads, and what it misses.

An array is a fixed set of probes for common, well-studied variants. Ours is a customised Global Screening Array. It is fast, affordable, and genuinely useful: ancestry, common tendencies across the areas you choose, and the everyday genetics of food, drink, sleep and movement. Its reach is then extended by imputation, which infers the common variants between the probes from a large reference panel, so we can compute polygenic risk scores across common variants. But imputation cannot conjure a rare variant that was never on the chip.

Whole-genome sequencing reads every base directly: short-read sequencing on an Illumina NovaSeq, with paired 150bp reads, inserts around 400bp, at about 35x mean depth. That is where the rare, high-impact variants live, the ones an array is blind to by design, along with larger structural changes and the deeper detail of how you handle medicines. It is not a different practice. It is a depth you can choose, with more of your DNA to read.

Side by side

A DNA array, and the whole genome.

DNA arrayWhole-genome sequencing
What it readsAbout a million pre-selected, well-studied positionsEvery base of your genome, about three billion
How it is readCustomised Global Screening Array, then imputedShort-read NovaSeq, ~150bp reads, ~35x mean depth
Common variantsYes, the well-studied onesYes, read directly
Rare and private variantsNo, only what is on the chipYes, including ones almost unique to you
Structural changesLarge gains and losses, not the finer detailYes, down to smaller indels and rearrangements
Medicine-handling detailThe common variantsFuller, including rarer ones
Ancestry and traitsYesYes
Starts from$690$2,900

Which depth fits you

The right depth is the honest one.

An array is enough when you want a clear, affordable read of the common picture: ancestry, the everyday genetics of how you live, and common-variant tendencies across the areas you choose.

Whole genome earns its cost when you want the depth an array cannot reach: the rare and private variants beyond its probes, the fullest detail on how you handle medicines, and the confidence of having read all of it rather than a sample.

Either way, the same precision medicine analyst reads your DNA by hand and writes the same kind of analysis. You choose the depth on the questionnaire: an array starts from $690, whole genome from $2,900. See how pricing works.

This is informational and educational, not clinical or diagnostic. Anything of clinical consequence is flagged plainly for you to bring to your own physician.

Choose your depth

Read the common picture, or all of it.

Tell us how deep you want to read. A precision medicine analyst replies with a proposal shaped around the depth and the areas you chose, not a template.