What you carry at this position in your DNA and what research says about it.
HDL Cholesterol Levels: 10/10 evidence, 72 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): C/C
Typical HDL and Higher Cardiovascular Risk
This genotype is associated with lower levels of protective HDL cholesterol and slightly higher triglycerides. It may also elevate the overall risk of developing metabolic syndrome.
What this genotype means: Lower baseline HDL cholesterol; Slightly higher triglycerides and LDL; Increased risk of metabolic syndrome.
Sample genotype (not yours): A/A
Highest HDL and Strong Cardiovascular Protection
Two copies of the A allele lead to significantly higher HDL cholesterol and lower triglycerides. This profile provides robust natural protection against metabolic syndrome.
What this genotype means: Highest baseline HDL cholesterol; Significantly lower triglycerides; Reduced risk of metabolic syndrome.
Sample genotype (not yours): C/A
Favorable Lipid Profile and Higher HDL
Carrying one copy of the protective A allele is linked to higher HDL cholesterol levels and lower triglycerides. This profile offers moderate natural protection against metabolic syndrome.
What this genotype means: Higher circulating HDL cholesterol; Favorable baseline triglyceride levels; Lower risk of metabolic syndrome.
Gene function and biological role
Gene Function: The CETP gene encodes the cholesteryl ester transfer protein, a key regulator of circulating lipid levels in the bloodstream [1]. This protein facilitates the exchange of cholesteryl esters from high-density lipoproteins (HDL) to very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL) [1]. Lower activity of the CETP protein typically results in higher levels of beneficial HDL cholesterol, often referred to as good cholesterol [2]. Conversely, higher CETP activity accelerates the clearance of HDL, leading to lower circulating levels of this protective lipid [1]. Because of its central role in lipid shuttling, CETP is a major target of interest for cardiovascular therapies [2].
Variant Impact: The rs3764261 variant is located in the promoter region of the CETP gene, directly influencing how much of the protein is produced [3]. The common C allele is associated with increased CETP gene expression, leading to more active protein and consequently lower HDL cholesterol levels [3]. The minor A allele reduces gene expression, resulting in less CETP protein, which allows HDL particles to persist longer in circulation [4]. This single-nucleotide change represents one of the strongest genetic influences on HDL cholesterol levels discovered in genome-wide association studies [3]. Beyond HDL, this genetic switch also subtly alters circulating triglycerides and LDL cholesterol levels [4].
Key Insight: This variant is the single strongest genetic predictor of HDL cholesterol levels in the human genome, and its effects can be significantly modified by dietary fat intake and weight management.
Location: CETP. Chromosome 16 · 16q13 · 57.0 Mb
Estimated prevalence by population
Global 47.7%; European 45.7%; African 46.1%; East Asian 69.7%; South Asian 44.2%; Americas 49.7%; Ashkenazi 55.7%; Finnish 52.3%; Middle Eastern 54.5%; Amish 37.4%.
Estimated CC genotype frequency.
Global 42.6%; European 43.8%; African 43.6%; East Asian 27.6%; South Asian 44.6%; Americas 41.6%; Ashkenazi 37.9%; Finnish 40.0%; Middle Eastern 38.7%; Amish 47.5%.
Estimated CA genotype frequency.
Global 9.7%; European 10.5%; African 10.3%; East Asian 2.7%; South Asian 11.2%; Americas 8.7%; Ashkenazi 6.5%; Finnish 7.6%; Middle Eastern 6.9%; Amish 15.1%.
Estimated AA genotype frequency.
Showing effects for C/C genotype
Cardiovascular & Metabolic
Lipids & Cholesterol
HDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Typical Levels.
Triglycerides. Evidence: 10/10. Source: PMID 20686565. Elevated Levels.
LDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Slightly Elevated.
Metabolic Syndrome & Insulin Resistance
Metabolic Syndrome. Evidence: 8/10. Source: PMID 20694148. Increased Risk.
Organ Systems
Vision & Eye Health
Macular Degeneration. Evidence: 8/10. Source: PMID 21665990. Typical Risk.
Showing effects for A/A genotype
HDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Highest Levels.
Triglycerides. Evidence: 10/10. Source: PMID 20686565. Lower Levels.
LDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Slightly Lower.
Metabolic Syndrome. Evidence: 8/10. Source: PMID 20694148. Lower Risk.
Macular Degeneration. Evidence: 8/10. Source: PMID 21665990. Increased Risk.
Showing effects for C/A genotype
HDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Higher Levels.
Triglycerides. Evidence: 10/10. Source: PMID 20686565. Typical Levels.
LDL Cholesterol. Evidence: 10/10. Source: PMID 20686565. Typical Levels.
Metabolic Syndrome. Evidence: 8/10. Source: PMID 20694148. Typical Risk.
Macular Degeneration. Evidence: 8/10. Source: PMID 21665990. Slightly Increased.
What this genotype means for the people who carry it
Sample genotype: CC (Homozygous)
Having two copies of the C allele is the most common genetic profile globally, resulting in typical baseline levels of the CETP protein [1]. This higher protein activity leads to faster clearance of protective HDL particles, resulting in lower circulating HDL cholesterol [1]. Clinical studies show this profile is also linked to slightly higher levels of LDL cholesterol and triglycerides [2]. Together, these lipid patterns contribute to a moderately higher susceptibility to metabolic syndrome [3]. Interestingly, research suggests that individuals with this genotype may experience a more pronounced improvement in their lipid profiles when adopting a low-carbohydrate, higher-fat diet compared to a low-fat diet [4].
Lower baseline HDL cholesterol; Slightly higher triglycerides and LDL; Increased risk of metabolic syndrome.
Sample genotype: AA (Homozygous)
Having two copies of the A allele results in the lowest levels of CETP protein expression, allowing HDL particles to remain in the bloodstream much longer [1]. This genetic profile is associated with the highest average levels of protective HDL cholesterol and significantly lower triglycerides [2]. Individuals with this genotype enjoy a naturally lower risk of developing metabolic syndrome and related cardiovascular complications [3]. However, this robust lipid protection comes with a minor trade-off, as the A allele is also linked to an increased risk of age-related macular degeneration [4]. Additionally, some research indicates that carriers of this genotype may experience a slightly reduced protective response to statin therapy regarding heart attack prevention, though overall cardiovascular risk remains low [5].
Highest baseline HDL cholesterol; Significantly lower triglycerides; Reduced risk of metabolic syndrome.
Sample genotype: CA (Heterozygous)
Carrying one copy of the A allele reduces the overall production of the CETP protein in the liver [1]. This moderate reduction in protein activity slows down the clearance of HDL particles, resulting in higher circulating levels of good cholesterol [2]. This genotype is also associated with favorable shifts in other blood lipids, including lower baseline triglycerides and slightly lower LDL cholesterol [2]. These combined lipid improvements contribute to a lower overall risk of metabolic syndrome [3]. While this profile is generally highly favorable for cardiovascular health, carrying the A allele is also associated with a very small increase in the risk of age-related macular degeneration, which is a common trade-off at this locus [4].
Higher circulating HDL cholesterol; Favorable baseline triglyceride levels; Lower risk of metabolic syndrome.
Variants with shared genetic architecture
rs12720922 · CETP Gene · Chr 16 · Cholesterol and Heart Health
rs1532624 · CETP Gene · Chr 16 · Lipid Levels and Statins
rs17231506 · CETP Gene · Chr 16 · Cardiovascular Health
A genetic map of human metabolism across the allele frequency spectrum.
Biological, clinical and population relevance of 95 loci for blood lipids.
A large electronic-health-record-based genome-wide study of serum lipids.
A genome-wide association study of the metabolic syndrome in Indian Asian men.
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