Genetic variant
rs857721
rs857721 is a single-letter difference in human DNA, on chromosome 1. Carrying it does not, on its own, mean you have or will develop any condition.
What is this?
Your DNA is a long sequence of four letters. At a few million positions, people commonly differ by a single letter; each of those positions is called a SNP (“snip”), and rs857721 is the catalogue number of one of them. Which letters you carry there — one copy from each parent — is your genotype.
We hold only the basic reference record for this variant: its ID and position. Many catalogued variants have never been linked to anything.
Why might it matter?
ClinVar holds no clinical classification for this variant. That is the usual case: most catalogued variants have no known effect on health.
Do I have this variant?
If you have taken a consumer DNA test (23andMe, AncestryDNA and similar), you can download its raw data file and check. Create a free account, upload the file, and this page will show the letters you carry at rs857721, if your test read this position.
Connect this with your blood results
A gene is a fixed instruction; a blood test shows what your body is doing now. CheckMyBloods reads the two side by side, so a variant can be set against the markers it could plausibly affect.
Blood markers do not diagnose a genetic condition, and a variant does not explain a blood result on its own. Together, with symptoms and family history, they give a clinician context.
What should I do next?
- Find out whether you carry it. Reading about a variant says nothing about you until you know your genotype.
- Put it in context. Add your blood results, so the variant can be read against what your body is doing.
- Ask questions. Dr. Hemsworth, our AI assistant, can explain this variant and your results in plain English.
- Take anything that worries you to a professional. A GP or genetic counsellor can order a confirmatory test and interpret it with your history.
This page is general information drawn from public research databases. It cannot diagnose anything, and it is not a substitute for advice from a doctor or genetic counsellor who knows your history.
Technical details
- dbSNP ID
- rs857721
- Position
- chr1:158642758
Genome-wide association studies (6)
| Trait | Risk allele | OR / beta | P-value | Study |
|---|---|---|---|---|
| Glycated hemoglobin levels | A | β 0.082 | 3E-194 | PubMed |
| Total bilirubin levels | A | β 0.025 | 2E-50 | PubMed |
| Total bilirubin levels | A | β 0.034 | 1E-36 | PubMed |
| Direct bilirubin levels | A | β 0.026 | 1E-18 | PubMed |
| Spleen volume | — | β 0.054 | 6E-12 | PubMed |
| Other erythrocyte phenotypes | A | β 0 | 1E-10 | PubMed |
Sources
- dbSNP: rs857721 — the reference record
- ClinVar — clinical interpretations submitted by laboratories
- SNPedia — community-written summaries
- GWAS Catalog — association studies