Free MTHFR raw data checker
Check MTHFR markers in your raw DNA file.
Drop in a 23andMe, AncestryDNA, or MyHeritage raw genotype file to see whether it contains MTHFR C677T rs1801133 and A1298C rs1801131. The scan runs locally in your browser and shows raw file values only.
Want to see the output first? Use the synthetic marker example.
This checker reports marker presence and the raw genotype string only. It does not classify alleles, diagnose conditions, recommend supplements, or send your genotype data to GenoSight.
What this checker looks for
The goal is narrow on purpose: answer whether selected raw-data markers are present before anyone tries to interpret them.
MTHFR C677T
Searches for rs1801133, the common C677T marker people usually mean when they ask about MTHFR raw data.
MTHFR A1298C
Searches for rs1801131, often discussed with C677T in folate and methylation conversations.
Related context
Also checks COMT rs4680 because single-SNP MTHFR interpretation can be misleading without adjacent methylation context.
Why the checker avoids interpretation
MTHFR is easy to overinterpret online. A raw genotype string can be strand-dependent, chip-dependent, and incomplete. GenoSight keeps this free page to marker presence and handles broader context inside the educational report.
See methylation report contextGuardrails
Useful without pretending to be clinical.
- Runs locally in your browser
- Shows raw genotype strings only
- Does not label alleles good, bad, normal, or mutation
- Does not recommend methylfolate, supplements, or medication changes
MTHFR raw data checker questions
Can I check MTHFR from 23andMe raw data?
Often, yes. This checker looks for the common MTHFR rsIDs rs1801133 and rs1801131 in compatible raw genotype files. Coverage can vary by provider and chip version.
Can I check MTHFR from AncestryDNA or MyHeritage raw data?
Yes, when the file is a compatible raw genotype download and includes the relevant markers. Missing coverage should not be treated as a medical negative result.
Does this page interpret my MTHFR genotype?
No. It only shows whether selected markers are present and what raw genotype string appears in the file. Interpretation belongs in broader context and should not be reduced to one SNP.
What should I run after checking the markers?
For GenoSight, Detox & Methylation is the most direct first report. It frames MTHFR alongside COMT, folate and B-vitamin context, goals, caveats, and source links.
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