23andMe MTHFR A1298C marker
MTHFR rs1801131 in 23andMe raw data.
If you are searching a 23andMe raw DNA file for MTHFR A1298C, the marker most people mean is rs1801131. GenoSight can help you check whether that marker is present, then keep the interpretation cautious inside a broader educational methylation report.
Start with marker coverage
Do this before interpreting the raw letters.
- Use the downloaded 23andMe raw genotype file, usually a zipped text file
- Search for rs1801131 in the raw-data text file or use a local marker checker
- Treat missing rs1801131 as a coverage issue, not proof that you do or do not have a variant
- Interpret A1298C with C677T, COMT, folate context, labs, symptoms, and clinician guidance
What to know before you search the file.
A raw-data search can answer a narrow coverage question. It cannot tell you, by itself, whether you have a methylation issue or need a supplement.
23andMe raw data is informational
23andMe says raw data has undergone general quality review, but only a subset of markers are individually validated and the data is not for medical or diagnostic use.
rs1801131 is one marker
rs1801131 is commonly discussed as MTHFR A1298C. It is usually considered alongside MTHFR C677T rs1801133 rather than as a standalone answer.
GenoSight separates detection from interpretation
The free checker can show whether rs1801131 appears in your file. A full report adds cautious methylation context without prescribing supplements.
Keep raw data inside its limits.
GenoSight is educational only. It can help you move from a raw marker lookup to a structured report, but medical decisions require clinical confirmation, labs, and a qualified professional.
23andMe raw data download
Explains raw-data access, informational-use limits, download timing, zipped text files, and third-party interpretation cautions.
23andMe raw-data technical details
Explains strand reporting, reference genome language, and uncalled variants shown as double dashes in downloaded raw data.
MedlinePlus MTHFR gene
Describes MTHFR and notes that C677T and 1298A>C are common studied polymorphisms while keeping medical context separate.
Next steps with a 23andMe file
Check rs1801131 locally
Use the browser-only checker to see whether the marker appears in your file without uploading it.
ContinueCompare rs1801133
Read the C677T marker page so A1298C is not interpreted in isolation.
ContinueRun Detox & Methylation
Use free signup credits to generate a broader educational report from a compatible raw file.
Continuers1801131 and 23andMe questions
Can I find rs1801131 in 23andMe raw data?
Often, but not always. 23andMe chip versions and no-call results can vary, so the right first step is checking whether your specific file contains rs1801131.
What does rs1801131 mean in MTHFR?
rs1801131 is commonly discussed as MTHFR A1298C. A raw genotype is not a methylation test, diagnosis, or supplement instruction, and it should be interpreted with C677T and broader clinical context.
What if my 23andMe file does not show rs1801131?
That usually means the marker is missing, uncalled, or represented differently in that file. It does not prove anything clinically by itself.
Can GenoSight analyze my 23andMe file for MTHFR?
Yes, if it is a compatible 23andMe raw genotype file. GenoSight can run an educational Detox & Methylation report that frames MTHFR with COMT, folate context, caveats, and source notes.