rs4276227

A SNP in the CMTM8 gene on chromosome 3. Its most notable genotype is C;C: 1.5x risk

Gene
CMTM8
Location
Chr 332,289,194 (GRCh38)
Highest magnitude
0.0Typical
Tested on
23andMe, AncestryDNA
Minor allele frequency
32%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CMost notableNot rated1.5x riskTypical · 0.052% of people
  2. C;TNot rated1.2x riskTypical · 0.037% of people
  3. T;TNot ratednormalTypical · 0.011% of people

On SNPedia: (C;C), (C;T), (T;T). 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.

  • AverageC;C 52% C;T 37% T;T 11%
  • European ancestry (Utah)C;C 43% C;T 50% T;T 7%
  • Han Chinese (Beijing)C;C 76% C;T 22% T;T 2%
  • Japanese (Tokyo)C;C 93% C;T 7% T;T 0%
  • Yoruba (Nigeria)C;C 37% C;T 46% T;T 17%
  • African ancestry (Southwest US)C;C 42% C;T 47% T;T 11%
  • Chinese (Denver)C;C 74% C;T 26% T;T 0%
  • Gujarati IndianC;C 65% C;T 29% T;T 6%
  • Luhya (Kenya)C;C 36% C;T 44% T;T 20%
  • Mexican ancestry (Los Angeles)C;C 16% C;T 45% T;T 40%
  • Maasai (Kenya)C;C 45% C;T 45% T;T 10%
  • TuscanC;C 44% C;T 49% T;T 7%

Conditions, medicines and genes

Notes

From SNPedia

Notes

rs4276227 has been reported in a large study to be associated with bipolar disorder. The risk allele (oriented to the dbSNP entry) is (C); the odds ratio associated with heterozygotes is 1.2 (CI 0.99-1.46), and for homozygotes, 1.49 (CI 1.23-1.81).

Source and license

Adapted from rs4276227 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.