rs1801260
A SNP in the CLOCK gene on chromosome 4. Its most notable genotype is G;G: Lower ADHD symptom scores.
- Gene
- CLOCK
- Location
- Chr 455,435,202 (GRCh38)
- Highest magnitude
- 2.0Worth knowing
- Tested on
- 23andMe, AncestryDNA, FamilyTreeDNA
- Minor allele frequency
- 22%
Genotypes
Plus strand, as in 23andMe and AncestryDNA files.
- G;GMost notableGoodLower ADHD symptom scores.
- A;GNot ratedNormal risk of ADHD symptoms.
- A;ABadNormal (higher) risk of ADHD symptoms.
SNPedia records rs1801260 on the minus strand: (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.
- AverageG;G 5% A;G 32% A;A 63%
- European ancestry (Utah)G;G 6% A;G 40% A;A 54%
- Han Chinese (Beijing)G;G 0% A;G 13% A;A 87%
- Japanese (Tokyo)G;G 2% A;G 36% A;A 62%
- Yoruba (Nigeria)G;G 3% A;G 22% A;A 74%
- African ancestry (Southwest US)G;G 0% A;G 33% A;A 67%
- Chinese (Denver)G;G <1% A;G 11% A;A 88%
- Gujarati IndianG;G 18% A;G 50% A;A 33%
- Luhya (Kenya)G;G 3% A;G 25% A;A 73%
- Mexican ancestry (Los Angeles)G;G 5% A;G 43% A;A 52%
- Maasai (Kenya)G;G 5% A;G 44% A;A 51%
- TuscanG;G 7% A;G 39% A;A 54%
Related
Conditions, medicines and genes
Notes
From SNPedia
Show notes, about 380 words
rs1801260, a SNP in the CLOCK gene known as 3111 T/C, has been reported to influence sleep and activity patterns in patients affected by bipolar depression. From this article's abstract: "Compared to T/T homozygotes, carriers of the C allele had a similar degree of severity of depression, but showed higher activity levels in the evening, a delayed sleep onset (mean 79 min later), and a reduced amount of sleep during the night (mean 75 min less)." Allele frequencies of T3111C SNP of hClock were significantly different between schizophrenics and controls (chi(2) = 19.738, P C combined genotype is associated with evening preference and weight loss resistance in a behavioral therapy treatment for obesity. "Circadian locomotor output cycles kaput (CLOCK) molecule plays major roles in circadian rhythmicity and regulates daily physiological processes including digestive activity. Therefore, we hypothesized that the CLOCK 3111T/C single nucleotide polymorphism (SNP) might have adverse effects on the regulation of gastric motility." "The clock molecule plays major roles in circadian rhythmicity and regulating lipid and glucose metabolism in peripheral organs. Disruption of the circadian rhythm can lead to cardiometabolic disorders." "Here, we find that cholecystokinin (Cck) is a direct transcriptional target of CLOCK and levels of Cck are reduced in the ventral tegmental area (VTA) of ClockΔ19 mice. Selective knockdown of Cck expression via RNA interference in the VTA of wild-type mice produces a manic-like phenotype" " C genetic variants in CLOCK 3111 T/C are more obese and lose less weight in a dietary and behavioral treatment for obesity than TT carriers and they are also more evening-type subjects " Attention-Deficit Hyperactivity Disorder
G;G
This is the rarer form of the CLOCK gene. In addition to possibly affecting evening preference, it has been linked to decreased Attention Deficit Hyperactivity Disorder symptoms.
A;G
This is one normal and one rare form of the CLOCK gene. In addition to possibly affecting evening preference, it has been linked to normal Attention Deficit Hyperactivity Disorder symptom scores.
A;A
This is the most common form of the CLOCK gene. In addition to possibly affecting evening preference, it has been linked to increased ADHD symptoms.
Source and license
Adapted from rs1801260 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.