A project by Brandon Saldan

Read the rest of your DNA test.

Twofold reads your DNA test's raw data and explains what it says about your susceptibility to health conditions, response to medicines, and traits from metabolism to personality.

  • Free and open source
  • No account needed
  • Nothing leaves your device

Accepts .txt, .csv, .zip, .gz and .vcf files. How to download your raw data

Your genotypes, ranked and explained.

Every match between your file and SNPedia, organized into a dashboard you can sort, filter and search. Nothing to pay for and nothing to sign up for.

Your most notable genotypes, first

Findings are ranked by SNPedia's magnitude, so the interesting results rise to the top. Each one explains what your genotype means and whether it is generally good or bad to have.

  • Magnitude from 0 to 10
  • Population frequencies
  • Linked research

Patterns that need more than one variant

Some traits only appear when several variants line up. Twofold checks every SNPedia genoset against your whole file and shows the combinations you match.

  • 283 genosets checked
  • Criteria you can inspect

Follow a thread through your results

Every finding links to the genes, conditions and medicines SNPedia connects it to, so you can move from one result to everything related.

  • Genes and conditions
  • Medicines and drug response

All examples come from the sample report, which uses a made-up genome. Open the sample report

Works with the test you already took.

Download the raw data file from your testing service and open it here exactly as it comes. ZIP and GZ files do not need to be unzipped.

  • 23andMe

    ZIP

    SettingsRequest raw data

    Full guide

  • AncestryDNA

    ZIP or TXT

    DNA SettingsDownload DNA Data

    Full guide

  • MyHeritage

    CSV

    Manage DNA kitsDownload

    Full guide

  • FamilyTreeDNA

    CSV.GZ

    Autosomal DNADownload Raw Data

    Full guide

  • Living DNA

    TXT

    ProfilesDownload

    Full guide

  • Whole genome

    VCF or VCF.GZ

    Files or downloadsVCF file

    Full guide

Look up any gene or SNP.

Every notable SNP has its own page, with what each genotype means, how common it is and which tests include it.

  • 23,475SNP pages
  • 3,826genes
  • 351conditions
  • 101medicines
Explore the database

Or browse conditions, medicines or genes

Questions

Is Twofold free?

Yes. There is no fee, account or subscription, and the source code is public on GitHub.

Is my DNA file uploaded?

No. Your file is read in your browser and never sent anywhere. Twofold has no upload endpoint, and it works offline after your first visit.

Which files can I use?

Raw data from 23andMe, AncestryDNA, MyHeritage, FamilyTreeDNA and Living DNA, plus VCF files from whole genome sequencing. ZIP and GZ files work without unzipping.

Where do the explanations come from?

From SNPedia, a community wiki of SNPs and genotypes, the same source Promethease uses. Twofold reads a dated snapshot of it.

Is this medical advice?

No. SNPedia entries can be incomplete or wrong, and consumer chips sometimes misread rare variants. Confirm important findings with a clinical test.

Coming from Promethease? See how Twofold compares.

Your raw data has more to say.

It takes a few seconds, and your file never leaves this browser.