What you carry at this position in your DNA and what research says about it.
HDL Cholesterol Levels: 8/10 evidence, 41 publications.
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Sample genotype (not yours): C/C
Lower HDL Cholesterol and Higher Heart Risk
Carrying two copies of the C allele is associated with lower levels of beneficial HDL cholesterol. This profile is linked to an elevated risk of coronary artery disease.
What this genotype means: Lower circulating HDL cholesterol; Increased risk of coronary artery disease; Slightly higher vitamin D levels.
Sample genotype (not yours): A/A
Higher HDL Cholesterol and Lower Heart Risk
Having two copies of the A allele is linked to significantly higher levels of HDL cholesterol. This lipid profile is associated with a reduced risk of developing coronary artery disease.
What this genotype means: Higher circulating HDL cholesterol; Reduced risk of coronary artery disease; Slightly lower vitamin D levels.
Sample genotype (not yours): C/A
Typical HDL Cholesterol and Moderate Heart Risk
Carrying one copy of each allele typically results in intermediate levels of both CETP protein and HDL cholesterol. This profile represents an average cardiovascular risk compared to the general population.
What this genotype means: Typical circulating HDL cholesterol; Average risk of coronary artery disease; Typical vitamin D levels.
Gene function and biological role
Gene Function: The CETP gene encodes the cholesteryl ester transfer protein, which plays a critical role in lipid metabolism [1]. This protein facilitates the exchange of lipids, specifically transferring cholesteryl esters from high-density lipoproteins to low-density lipoproteins [1]. Through this process, CETP directly influences circulating levels of HDL, often referred to as the good cholesterol [2]. Variations in this gene can alter the rate of lipid transfer, thereby modifying cardiovascular risk profiles [2].
Variant Impact: The rs1800775 variant is located in the promoter region of the CETP gene, where it directly influences gene expression [3]. The change from a cytosine to an adenine at this position reduces the transcription of the CETP protein [3]. Lower levels of active CETP slow down the clearance of cholesteryl esters from HDL particles [3]. Consequently, this molecular slowdown leads to a significant increase in circulating HDL cholesterol levels in the blood [4].
Key Insight: This variant acts like a natural brake on the CETP protein, allowing beneficial HDL cholesterol to circulate longer in the bloodstream.
Location: CETP. Chromosome 16 · 16q13 · 57.0 Mb
Estimated prevalence by population
Global 23.0%; European 26.0%; African 18.0%; East Asian 25.2%; South Asian 16.0%; Americas 24.4%; Ashkenazi 24.6%; Finnish 24.1%; Middle Eastern 26.0%; Amish 12.1%.
Estimated CC genotype frequency.
Global 49.6%; European 50.0%; African 48.9%; East Asian 50.0%; South Asian 48.0%; Americas 50.0%; Ashkenazi 50.0%; Finnish 50.0%; Middle Eastern 50.0%; Amish 45.3%.
Estimated CA genotype frequency.
Global 27.4%; European 24.1%; African 33.1%; East Asian 24.9%; South Asian 36.1%; Americas 25.6%; Ashkenazi 25.4%; Finnish 25.9%; Middle Eastern 24.0%; Amish 42.6%.
Estimated AA genotype frequency.
Showing effects for C/C genotype
Cardiovascular & Metabolic
Lipids & Cholesterol
HDL Cholesterol. Evidence: 8/10. Source: PMID 17463246. Lower Levels.
Apolipoprotein A1. Evidence: 4/10. Source: PMID 17463246. Higher Levels.
Heart Disease
Coronary Artery Disease. Evidence: 6/10. Source: PMID 29212778. Higher Risk.
Nutrition & Metabolism
Vitamin & Mineral Metabolism
Vitamin D Levels. Evidence: 8/10. Source: PMID 32059762. Higher Levels.
Showing effects for A/A genotype
HDL Cholesterol. Evidence: 8/10. Source: PMID 17463246. Higher Levels.
Apolipoprotein A1. Evidence: 4/10. Source: PMID 17463246. Lower Levels.
Coronary Artery Disease. Evidence: 6/10. Source: PMID 29212778. Lower Risk.
Vitamin D Levels. Evidence: 8/10. Source: PMID 32059762. Lower Levels.
Showing effects for C/A genotype
HDL Cholesterol. Evidence: 8/10. Source: PMID 17463246. Typical Levels.
Apolipoprotein A1. Evidence: 4/10. Source: PMID 17463246. Typical Levels.
Coronary Artery Disease. Evidence: 6/10. Source: PMID 29212778. Typical Risk.
Vitamin D Levels. Evidence: 8/10. Source: PMID 32059762. Typical Levels.
What this genotype means for the people who carry it
Sample genotype: CC (Homozygous)
Inheriting two copies of the C allele is associated with higher expression of the CETP protein, which accelerates the clearance of cholesterol from HDL particles [1]. This rapid transfer results in lower circulating levels of protective HDL cholesterol in the blood [1]. Multiple clinical studies have linked this genotype to an increased susceptibility to coronary artery disease and heart attacks [2]. On the other hand, this genetic setup is associated with higher levels of apolipoprotein A1 and slightly higher vitamin D levels [1] [3]. Managing cardiovascular health through lifestyle factors remains particularly important for individuals with this genetic profile.
Lower circulating HDL cholesterol; Increased risk of coronary artery disease; Slightly higher vitamin D levels.
Sample genotype: AA (Homozygous)
Inheriting two copies of the A allele leads to reduced expression of the CETP protein, which slows the transfer of cholesterol away from HDL particles [1]. As a result, circulating levels of beneficial HDL cholesterol remain elevated in the bloodstream [1]. Large-scale genetic studies have consistently linked this specific genotype to a lower risk of coronary artery disease and myocardial infarction [2]. Additionally, this genetic profile is associated with lower levels of apolipoprotein A1 and slightly lower vitamin D levels [1] [3]. Understanding these genetic tendencies can help tailor cardiovascular wellness strategies.
Higher circulating HDL cholesterol; Reduced risk of coronary artery disease; Slightly lower vitamin D levels.
Sample genotype: CA (Heterozygous)
Having one C allele and one A allele results in a balanced genetic influence on lipid transfer processes [1]. The presence of the A allele slightly reduces CETP activity, while the C allele maintains typical transfer rates [1]. Consequently, circulating HDL cholesterol levels and coronary artery disease risk generally align with population averages [2]. This intermediate state also extends to other associated traits, such as vitamin D and apolipoprotein A1 levels, which remain within typical ranges [3] [1]. It represents a common genetic baseline that does not strongly skew cardiovascular risk in either direction.
Typical circulating HDL cholesterol; Average risk of coronary artery disease; Typical vitamin D levels.
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
Genome-wide association analysis identifies loci for type 2 diabetes and triglyceride levels.
Genome-wide Association Study for Vitamin D Levels Reveals 69 Independent Loci.
Content updated August 2026.
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