rs12587781

A SNP in the TRA@ gene on chromosome 14. Its most notable genotype is G;T: 1.79x increased risk for narcolepsy in Europeans and 1.34x in Asians

Gene
TRA@
Location
Chr 1422,530,666 (GRCh38)
Highest magnitude
0.0Typical
Tested on
23andMe, AncestryDNA, FamilyTreeDNA
Minor allele frequency
29%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. G;TMost notableBad1.79x increased risk for narcolepsy in Europeans and 1.34x in AsiansTypical · 0.031% of people
  2. T;TNot ratedNo summary available.Typical · 0.055% of people

On SNPedia: (G;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.

  • AverageG;T 31% T;T 55%
  • European ancestry (Utah)G;T 26% T;T 72%
  • Han Chinese (Beijing)G;T 50% T;T 12%
  • Japanese (Tokyo)G;T 43% T;T 12%
  • Yoruba (Nigeria)G;T 16% T;T 83%
  • African ancestry (Southwest US)G;T 21% T;T 79%
  • Chinese (Denver)G;T 43% T;T 13%
  • Gujarati IndianG;T 32% T;T 61%
  • Luhya (Kenya)G;T 16% T;T 85%
  • Mexican ancestry (Los Angeles)G;T 41% T;T 55%
  • Maasai (Kenya)G;T 26% T;T 72%
  • TuscanG;T 32% T;T 64%

Conditions, medicines and genes

Notes

From SNPedia

Notes

23andMe blog Each copy of the G version of rs12587781 increased the odds of narcolepsy by 1.79 times in Europeans and 1.34 times in Asians. The G version of rs12587781 showed a trend towards increased odds of narcolepsy for African Americans, but the results were not statistically significant.

Source and license

Adapted from rs12587781 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.