rs17782313
MC4R, appetite regulation
What this position does
MC4R sits at the centre of the brain circuit that decides when you feel full. Rare severe mutations in it cause childhood obesity; this common variant nearby nudges appetite in the same direction, far more gently.
What each result means
| If you carry | What it means |
|---|---|
| No copies of the effect version TT | You have the lower-appetite version on both copies Two copies of the lower-appetite-associated version. |
| One copy CT | One copy of the higher-appetite version Associated with a small average increase in body weight and in reported hunger. |
| Two copies CC | Two copies of the higher-appetite version Associated with the largest average effect at this locus, still under two pounds. |
How common each version is
| Ancestry group | C (the effect version) | |
|---|---|---|
| African | 27.8% | |
| American | 13.4% | |
| East Asian | 18.7% | |
| European | 24.0% | |
| South Asian | 32.0% |
1000 Genomes Project phase 3, via Ensembl, retrieved 2026-09-23. These groupings are coarse and flatten a great deal of internal diversity, particularly within Africa. A variant being common somewhere tells you where a piece of your ancestry probably comes from, and nothing else.
How many people carry each result
| Ancestry group | TT | CT | CC |
|---|---|---|---|
| African | 339 / 661 | 277 / 661 | 45 / 661 |
| European | 292 / 503 | 181 / 503 | 30 / 503 |
| East Asian | 331 / 504 | 158 / 504 | 15 / 504 |
| South Asian | 227 / 489 | 211 / 489 | 51 / 489 |
| American | 264 / 347 | 73 / 347 | 10 / 347 |
Counts of people, not modelled frequencies: every one of the 2,504 individuals sequenced by the 1000 Genomes Project phase 3, tallied by the genotype they carry. Deriving these from allele frequencies instead would assume random mating inside each group and undercount the homozygotes.
How to find out which you have
If you have taken a test with 23andMe, AncestryDNA, MyHeritage, Family Tree DNA, TellMeGen or Living DNA, this position is very likely already in the raw data file they gave you. You do not need another test.
One thing to watch if you look it up by hand: testing companies report some positions from one DNA strand and some from the other, and the file does not say which. Read the letters as they appear and you will get the opposite of the truth for some positions. Sequencings resolves that automatically.
Source
Coordinates and allele pair verified against Ensembl GRCh37. Direction of effect verified against VEP protein consequences or 1000 Genomes population frequency. Category: Health-adjacent.
Where this fits
Common questions
What is rs17782313?
rs17782313 is a position in the near MC4R gene on chromosome 18. MC4R sits at the centre of the brain circuit that decides when you feel full. Rare severe mutations in it cause childhood obesity; this common variant nearby nudges appetite in the same direction, far more gently.
What does it mean if I have CC at rs17782313?
Two copies of the higher-appetite version. Associated with the largest average effect at this locus, still under two pounds.
What does it mean if I have TT at rs17782313?
You have the lower-appetite version on both copies. Two copies of the lower-appetite-associated version.
How do I find out my rs17782313 genotype?
If you have taken a home DNA test, this position is very likely in the raw data file you were given. Sequencings reads that file in your browser without uploading it, and resolves which DNA strand each position was reported from, which is the step most manual lookups get wrong.
This is reference information, not medical advice, and not a diagnosis. See the medical disclaimer. Category: Health-adjacent.