rs12970134

A SNP in the MC4R gene on chromosome 18. Its most notable genotype is A;A: adult waist 1.8cm larger on average

Gene
MC4R
Location
Chr 1860,217,517 (GRCh38)
Highest magnitude
0.0Typical
Tested on
23andMe, AncestryDNA
Minor allele frequency
20%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. A;AMost notableBadadult waist 1.8cm larger on averageTypical · 0.05% of people
  2. A;GBadadult waist 0.9cm larger on averageTypical · 0.032% of people
  3. G;GGoodnormalTypical · 0.064% of people

On SNPedia: (A;A), (A;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Frequency

Share of each genotype in 11 HapMap populations.

  • AverageA;A 5% A;G 32% G;G 64%
  • European ancestry (Utah)A;A 4% A;G 49% G;G 48%
  • Han Chinese (Beijing)A;A 3% A;G 30% G;G 67%
  • Japanese (Tokyo)A;A 4% A;G 32% G;G 64%
  • Yoruba (Nigeria)A;A 3% A;G 27% G;G 69%
  • African ancestry (Southwest US)A;A 2% A;G 23% G;G 75%
  • Chinese (Denver)A;A 3% A;G 27% G;G 71%
  • Gujarati IndianA;A 9% A;G 41% G;G 51%
  • Luhya (Kenya)A;A 4% A;G 18% G;G 78%
  • Mexican ancestry (Los Angeles)A;A 9% A;G 29% G;G 62%
  • Maasai (Kenya)A;A 3% A;G 28% G;G 69%
  • TuscanA;A 8% A;G 47% G;G 45%

Conditions, medicines and genes

Notes

From SNPedia

Show notes, about 270 words

A study of 14,000 Indian Asian or Caucasian adults indicates that rs12970134(A) alleles are associated with obesity. The average increase in waist circumference is 0.9cm BMI units per risk allele. see also blog.23andme.com The common obesity variant near MC4R gene is associated with higher intakes of total energy and dietary fat, weight change and diabetes risk in women. Variants near MC4R are associated with obesity and influence obesity-related quantitative traits in a population of middle-aged people: studies of 14,940 Danes. Investigation of the locus near MC4R with childhood obesity in Americans of European and African ancestry. The role of obesity-associated loci identified in genome-wide association studies in the determination of pediatric BMI. Large effects on body mass index and insulin resistance of fat mass and obesity associated gene (FTO) variants in patients with polycystic ovary syndrome (PCOS). From monogenic to polygenic obesity: recent advances. A genome-wide association study of the metabolic syndrome in Indian Asian men. Obesity and diabetes genes are associated with being born small for gestational age: results from the Auckland Birthweight Collaborative study. FTO and MC4R gene variants are associated with obesity in polycystic ovary syndrome. Common variants near MC4R: exploring gender effects in overweight and obese children and adolescents participating in a lifestyle intervention. A variant near the melanocortin-4 receptor gene regulates postprandial lipid metabolism in a healthy Caucasian population.

Source and license

Adapted from rs12970134 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.

SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.