What you carry at this position in your DNA and what research says about it.
Heart and Gallstone Risk: 9/10 evidence, 34 publications.
You're viewing every possible genotype for this variant.
None of these is your result. Use the genotype toggle to compare them, then sign up and upload your DNA to see which one is yours.
Sample genotype (not yours): G/G
Higher Heart Risk and Lower Gallstone Risk
Elevated blood cholesterol levels characterize this genetic profile, leading to a slightly higher risk of heart disease. Conversely, a protective effect is observed against the development of painful gallstones.
What this genotype means: Higher LDL and total cholesterol levels; Slightly increased risk of coronary artery disease; Lower risk of developing gallstones.
Sample genotype (not yours): G/T
Typical Heart and Gallstone Risk
Average blood lipid levels and typical risks for both heart disease and gallstones are expected with this balanced profile. Standard lifestyle habits are generally sufficient to maintain optimal health.
What this genotype means: Typical blood cholesterol levels; Average risk of coronary artery disease; Typical risk of gallstone formation.
Sample genotype (not yours): T/T
Lower Heart Risk but Higher Gallstone Risk
Reduced cardiovascular risk and lower blood cholesterol levels are key benefits of this genetic profile. However, a higher likelihood of developing painful gallstones is also present.
What this genotype means: Lower LDL and total cholesterol levels; Reduced risk of coronary artery disease; Increased risk of developing gallstones.
Gene function and biological role
Gene Function: ABCG8 encodes a half-transporter that partners with ABCG5 to form a functional sterol transporter [1]. This transporter is primarily expressed in the liver and intestines, where it pumps cholesterol and plant sterols out of the body [2]. In the liver, it secretes cholesterol into bile, while in the intestine, it limits the absorption of dietary sterols [2]. Proper function of this gene is crucial for maintaining healthy blood lipid levels [3].
Variant Impact: Altered blood lipid levels and cardiovascular health are strongly linked to the intronic rs4299376 variant [3]. The G allele is associated with higher circulating LDL and total cholesterol levels, which in turn increases the risk of coronary artery disease [4]. Conversely, the T allele promotes greater cholesterol secretion into bile, lowering blood cholesterol but increasing the risk of gallstones [5]. This genetic variation highlights a direct physiological trade-off between heart health and gallbladder function [5].
Key Insight: This variant presents a classic evolutionary trade-off: the same genetic copy that protects your heart by lowering blood cholesterol actually increases your risk of developing painful gallstones.
Location: ABCG8. Chromosome 2 · 2p21 · 43.8 Mb
Estimated prevalence by population
Global 6.7%; European 10.2%; African 2.5%; East Asian < 0.1%; South Asian 5.8%; Americas 5.7%; Ashkenazi 7.4%; Finnish 4.3%; Middle Eastern 11.6%; Amish 12.1%.
Estimated GG genotype frequency.
Global 35.6%; European 43.5%; African 26.6%; East Asian 1.2%; South Asian 36.5%; Americas 36.4%; Ashkenazi 39.6%; Finnish 32.9%; Middle Eastern 44.9%; Amish 45.4%.
Estimated GT genotype frequency.
Global 57.7%; European 46.3%; African 70.8%; East Asian 98.8%; South Asian 57.8%; Americas 57.9%; Ashkenazi 53.0%; Finnish 62.8%; Middle Eastern 43.5%; Amish 42.6%.
Estimated TT genotype frequency.
Showing effects for G/G genotype
Cardiovascular & Metabolic
Heart Disease
Heart Disease. Evidence: 9/10. Source: PMID 28714975. ~1.06x Risk.
Lipids & Cholesterol
LDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Elevated LDL.
Total Cholesterol. Evidence: 10/10. Source: PMID 20686565. Elevated.
Organ Systems
Digestive & Gut Disorders
Gallstones. Evidence: 8/10. Source: PMID 37705021. Reduced Risk.
Showing effects for G/T genotype
Heart Disease. Evidence: 9/10. Source: PMID 28714975. Typical Risk.
LDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Typical LDL.
Total Cholesterol. Evidence: 10/10. Source: PMID 20686565. Typical.
Gallstones. Evidence: 8/10. Source: PMID 37705021. Typical Risk.
Showing effects for T/T genotype
Heart Disease. Evidence: 9/10. Source: PMID 28714975. Reduced Risk.
LDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Lower LDL.
Total Cholesterol. Evidence: 10/10. Source: PMID 20686565. Lower.
Gallstones. Evidence: 8/10. Source: PMID 37705021. Increased Risk.
What this genotype means for the people who carry it
Sample genotype: GG (Homozygous)
Inheriting two copies of the G allele is linked to elevated levels of low-density lipoprotein (LDL) and total cholesterol in the bloodstream [1]. Because less cholesterol is transported out of the liver and into the bile, circulating lipids remain higher, which can contribute to plaque buildup in the arteries over time [2]. This process increases the overall risk of coronary artery disease [3]. On the positive side, because less cholesterol enters the gallbladder, the bile is less likely to become supersaturated [4]. This significantly reduces the likelihood of cholesterol crystallization, lowering the risk of painful gallstones [4]. Cardiovascular health remains the primary focus for individuals with this profile.
Higher LDL and total cholesterol levels; Slightly increased risk of coronary artery disease; Lower risk of developing gallstones.
Sample genotype: GT (Heterozygous)
A balanced middle ground for cholesterol transport is maintained by this heterozygous profile. With one G allele and one T allele, the body exhibits typical rates of biliary cholesterol secretion and intestinal absorption [1]. Blood levels of LDL and total cholesterol generally fall within the average range for the population [2]. The risk of developing coronary artery disease is not significantly elevated or reduced compared to the general baseline [3]. Similarly, the risk of gallstone formation remains at a typical level, as bile saturation is average [4]. Standard heart-healthy habits and a balanced diet are highly effective for overall wellness.
Typical blood cholesterol levels; Average risk of coronary artery disease; Typical risk of gallstone formation.
Sample genotype: TT (Homozygous)
Highly efficient transport of cholesterol out of the bloodstream and into the bile is promoted by carrying two copies of the T allele [1]. This active clearance results in significantly lower levels of circulating LDL and total cholesterol [2]. Consequently, the risk of developing coronary artery disease is reduced [3]. However, the high volume of cholesterol pumped into the gallbladder can supersaturate the bile [4]. When cholesterol levels in the bile exceed what bile salts can dissolve, it crystallizes and forms gallstones [4]. Gallbladder-supportive habits, such as eating a high-fiber diet and maintaining a stable weight, are particularly beneficial.
Lower LDL and total cholesterol levels; Reduced risk of coronary artery disease; Increased risk of developing gallstones.
Variants with shared genetic architecture
rs11887534 · ABCG8 Gene · Chr 2 · Gallstone Risk
rs4245791 · ABCG8 Gene · Chr 2 · Gallstone Risk
rs6544713 · ABCG8 Gene · Chr 2 · Heart Disease Risk
Polygenic Hyperlipidemias and Coronary Artery Disease Risk.
Biological, clinical and population relevance of 95 loci for blood lipids.
Content updated August 2026.
ReadYourDNA provides educational interpretation of DNA data you already have. It is not diagnostic, not a substitute for professional medical advice, diagnosis, or treatment, and is not intended to diagnose, treat, cure, or prevent any disease. Talk to a clinician before acting on any result.
Raw DNA Data Reports for 23andMe & AncestryDNA · About ReadYourDNA · FAQ · Methodology & Science · Pricing · Support and complaints · Legal & Contact · Health Traits · Pharmacogenomics · Carrier Status · Variant Explorer · The Human Karyotype · Privacy Policy · Terms of Service · Accessibility · Consumer Health Data Privacy · Your Privacy Choices · Editorial Standards · Your Data, Checkable · Sample Report · ReadYourDNA and Promethease compared · What is inside a 23andMe raw data file · What is inside an AncestryDNA raw data file · What a chatbot can and cannot do with your raw DNA file · Where a raw DNA file can still be uploaded in 2026
Written, maintained and operated by Martin Pechhacker, sole proprietor, Vienna, Austria. Trade register GISA 40064420. support@readyourdna.com