rs104894574

A SNP in the HCRT gene on chromosome 17. Its most notable genotype is A;C: Narcolepsy

Gene
HCRT
Location
Chr 1742,184,503 (GRCh38)
Highest magnitude
4.0Very important
Tested on
AncestryDNA

Genotypes

Plus strand, as in 23andMe and AncestryDNA files.

  1. A;CMost notableBadNarcolepsyVery important · 4.0
  2. A;AGoodcommon in clinvarTypical · 0.0

SNPedia records rs104894574 on the minus strand: (G;T), (T;T). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Conditions, medicines and genes

Notes

From SNPedia

Notes

rs104894574, also known as Leu16Arg or L16R, is a SNP in the hypocretin (orexin) neuropeptide precursor HCRT gene. In (just) one heterozygous individual, this SNP has been associated with a severe form of narcolepsy.

A;C

One report associates this genotype with a severe form of narcolepsy.

Source and license

Adapted from rs104894574 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.