Evidence · Replicated

What the research found

In the cited research, the A allele at rs17685 was associated with slightly more cups of coffee a day among coffee drinkers.

GG: Fewer cups
AG: Middle
AA: More cups

Slight effect

What the study found

In the study, each copy went with cups of coffee a day among coffee drinkers about 0.07 cups a day higher on average.

Coffee drinkers of European and African American ancestry, all discovery and replication cohorts combined · 115,465 people · Table 1, rs17685 row, trans-ethnic meta-analysis columns (effect from the random-effects meta-analysis of all stage 1 and stage 2 studies, footnote c; n in the row's last column)

Evidence: Genome-wide meta-analysis with independent replication
Who was studied: European ancestry, with African American follow-up

1000 Genomes Project

How common each genotype is

How common each genotype is in the 1000 Genomes Project, by region
Region	GGFewer cups	AGMiddle	AAMore cups
All regions2,504 people	54%	39%	8%
Africa661 people	68%	30%	2%
The Americas347 people	63%	32%	5%
East Asia504 people	42%	46%	12%
Europe503 people	50%	42%	8%
South Asia489 people	44%	45%	11%

Among the 2,504 people of the 1000 Genomes Project, in five world regions. These percentages describe groups of people, never anyone’s chance of having a trait.

Ancient genomes

Through time

How often the studied letter was read in ancient people, era by era, in the region chosen.

Region

Through time: Europe
Before farmingbefore 6500 BC	47%14 of 30 copies read
First farmers6500 to 3000 BC	26%59 of 228 copies read
Bronze Age3000 to 1200 BC	26%34 of 130 copies read
Iron Age and Antiquity1200 BC to AD 600	31%88 of 282 copies read
Middle AgesAD 600 to 1500	31%82 of 267 copies read
Today1000 Genomes	29%291 of 1,006 copies

Neanderthal and Denisovan genomes

Altai Neanderthal: Not read
Vindija Neanderthal: Not read
Chagyrskaya Neanderthal: No copies
Denisovan: Not read

For most ancient people only one of their two copies can be read, so these counts are copies read, not people. Close relatives, repeated samples and samples the archive marks as unreliable are left out. Damage in old DNA can fake this letter, so it is counted only from samples treated to remove that damage and from high-quality genomes. Ancient genomes from the Allen Ancient DNA Resource (AADR v66): 15,136 people.

rs17685

The marker

Gene or region: POR
Marker: rs17685
Location: Chromosome 7 · GRCh37 75,616,105 · GRCh38 75,986,787
Letters studied: A and G, with A as the studied allele

A DNA Traits report reads this marker in your raw DNA file and shows which of the three genotypes is yours, with how common it is. It counts the copies of the studied allele; it does not measure the trait itself.

Marker: POR · rs17685
Location: Chromosome 7 · GRCh37 75,616,105 · GRCh38 75,986,787
Studied allele: A
Published statistic: Per A, cups a day (Cornelis 2015 Table 1): stage 1 0.07 (SE 0.01), P 9.06e-14 (EUR n <= 91,462); stage 2 European 0.05 (0.01), P 1.01e-3 (n <= 30,062); African American 0.07 (0.03), P 7.55e-3 (n <= 7,964); all stages 0.07 (0.01), log10 Bayes factor 15.12, n 115,465. UK Biobank combined caffeine intake from coffee and tea: beta -0.0408 SD per G, P 3.8e-56 (Said 2020 Table S12); bitter beverages joint P 1.02e-16 (Zhong 2019 Table 2) (Table 1, rs17685 row, trans-ethnic meta-analysis columns (effect from the random-effects meta-analysis of all stage 1 and stage 2 studies, footnote c; n in the row's last column))
1000 Genomes Project phase 3, people with 0, 1 and 2 copies: All regions 1346 / 970 / 188 · Africa 451 / 195 / 15 · The Americas 219 / 112 / 16 · East Asia 211 / 231 / 62 · Europe 252 / 211 / 40 · South Asia 213 / 221 / 55

See this card in the sample report

Limits

What it cannot tell you

Intake was reported as cups a day by people who drink coffee.

Genome-wide meta-analysis identifies six novel loci associated with habitual coffee consumption (Coffee and Caffeine Genetics Consortium, Cornelis et al., 2015)

The same topic

More in Nutrition & metabolism

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