What can your raw DNA file tell you about coeliac disease?
The HLA-DQ markers behind coeliac disease are unusual in consumer genetics — a negative result is far more informative than a positive one. Here is why, and what the file can support.
Blog
Practical writing about consumer DNA data: how to get your file, what is actually in it, and what can and cannot be worked out from it.
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CYP2C19 and clopidogrel — what a pharmacogenomic result actually means
Of everything readable from a consumer DNA file, how you process clopidogrel has the clearest practical use. What the star alleles mean, and what to do with the result.
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What can you get from your raw DNA data for free?
A tour of what free DNA interpretation actually covers, where the free tier usually stops, and which questions are worth checking yourself before paying anyone.
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MTHFR in your raw DNA data — what a C677T result actually means
MTHFR is the most widely reported gene in consumer DNA interpretation, and the one where the gap between those reports and the mainstream genetics position is widest.
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Whole genome sequencing vs a DNA array file — what actually differs
Consumer DNA kits produce array files. Sequencing produces something categorically different. Here is what each one can support, and when the upgrade is and is not worth it.
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What does carrier status mean in a DNA report?
Being a carrier says nothing about your own health and everything about a decision two people might make together. What the term means, and what a consumer file can and cannot show.
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What is a polygenic risk score, and can your raw DNA file produce one?
Polygenic scores are the headline feature of most premium DNA report tiers. What they measure, why the same score behaves differently across ancestries, and how to read one honestly.
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Why do two DNA services give different health results from the same file?
Upload one raw file to two services and the reports will differ. The reasons are structural rather than accidental, and knowing them tells you which report to trust.
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What your raw DNA file says about caffeine — CYP1A2 and rs762551
One well-studied marker separates fast from slow caffeine metabolisers. Here is what the research supports, what it does not, and how to find the marker in your own file.
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How to read your raw DNA file — rsid, chromosome, position and genotype
Your raw DNA file is a plain text table with four columns. Here is what each one means, how to look up one of your own markers, and what the letters do and do not tell you.
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Is it safe to upload your raw DNA data?
What can actually go wrong when you upload a genotype file, what to check in a service's privacy policy before you do, and what proper deletion looks like.
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Can your raw DNA file tell you if you are lactose intolerant?
One marker explains lactase persistence in European populations and misses it entirely in several others. A clear example of why coverage matters more than the result.
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What to do with your raw DNA data in 2026
You have the file. Here is what it can be used for, what the services that read it cost, which formats they take, and how to pick one without regretting it.
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How to download your raw DNA data from 23andMe
A step-by-step guide to exporting your raw genotype file from 23andMe, what the file actually contains, and what the columns mean.
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23andMe vs AncestryDNA vs MyHeritage — what their raw data files actually contain
The raw genotype files from the major consumer DNA services differ in format, marker count and coverage. Here is what each one gives you and why it matters.