Genetic variant

rs781637955 a variant in the MSTO1 gene

rs781637955 is a single-letter difference in the MSTO1 gene, on chromosome 1. ClinVar, the public archive of variant interpretations, lists it as likely pathogenic: probably able to cause or contribute to disease. 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 rs781637955 is the catalogue number of one of them, in the MSTO1 gene. Which letters you carry there — one copy from each parent — is your genotype.

MSTO1 (misato mitochondrial distribution and morphology regulator 1): Involved in mitochondrion distribution; mitochondrion organization; and positive regulation of mitochondrial fusion. Located in mitochondrial outer membrane. Is active in cytosol. [provided by Alliance of Genome Resources, Jul 2025]

Gene description from NCBI Gene

Why might it matter?

ClinVar records this variant as likely pathogenic, meaning probably able to cause or contribute to disease. A classification describes the variant, not you: what it means for one person depends on their genotype, their family history and often on other genes and circumstances.

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 rs781637955, 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?

  1. Find out whether you carry it. Reading about a variant says nothing about you until you know your genotype.
  2. Put it in context. Add your blood results, so the variant can be read against what your body is doing.
  3. Ask questions. Dr. Hemsworth, our AI assistant, can explain this variant and your results in plain English.
  4. 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
rs781637955
Gene
MSTO1
Position
chr1:155611292
ClinVar classification
Likely pathogenic

Sources