What you carry at this position in your DNA and what research says about it.
HDL Cholesterol Levels: 10/10 evidence, 21 publications.
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Sample genotype (not yours): G/G
Higher HDL Cholesterol and Lower Cardiovascular Risk
Elevated levels of HDL, often called good cholesterol, are characteristic of this genetic profile. This lipid balance is linked to a slightly lower risk of developing cardiovascular disease.
What this genotype means: Higher HDL cholesterol levels; Slightly lower cardiovascular risk; Higher apolipoprotein A1 levels.
Sample genotype (not yours): A/A
Lower HDL Cholesterol and Higher Cardiovascular Risk
Reduced levels of HDL, or good cholesterol, are characteristic of this genetic profile. This lipid balance is linked to a slightly higher risk of cardiovascular disease.
What this genotype means: Lower HDL cholesterol levels; Slightly higher cardiovascular risk; Lower apolipoprotein A1 levels.
Sample genotype (not yours): A/G
Typical HDL Cholesterol and Cardiovascular Risk
Average levels of HDL cholesterol are typical for this genetic profile. Cardiovascular risk and lipid transport function remain typical of the general population.
What this genotype means: Typical HDL cholesterol levels; Average cardiovascular risk; Typical apolipoprotein A1 levels.
Gene function and biological role
Gene Function: The CETP gene encodes the cholesteryl ester transfer protein, a key regulator of lipid metabolism in the bloodstream [1]. This protein facilitates the exchange of cholesteryl esters from high-density lipoprotein (HDL, or good cholesterol) to low-density and very-low-density lipoproteins [1] [2]. By transferring these lipids, CETP directly influences the balance and size of circulating cholesterol particles [2]. Genetic variations that alter CETP activity can significantly raise or lower circulating HDL levels [1] [3]. Consequently, CETP is a major focus of research for cardiovascular disease prevention and therapeutic drug development [3].
Variant Impact: The rs9989419 variant is a regulatory genetic marker located near the CETP gene on chromosome 16 [4]. This variant acts as a strong genetic proxy for CETP activity and is highly associated with blood lipid profiles across diverse global populations [4] [5]. The change alters the expression of the CETP protein, thereby modifying the rate at which cholesterol is transferred between lipoprotein particles [5]. This regulatory shift directly impacts the concentration of circulating HDL cholesterol and its primary protein component, apolipoprotein A1 [5] [6]. Understanding this variant helps clarify genetic influences on lipid transport and overall cardiovascular health [6].
Key Insight: This variant is one of the strongest genetic determinants of HDL cholesterol levels across multiple ancestries. It influences not just the amount of cholesterol, but the actual size and distribution of HDL particles.
Location: CETP. Chromosome 16 · 16q13 · 57.0 Mb
Estimated prevalence by population
Global 20.4%; European 15.4%; African 35.6%; East Asian 5.7%; South Asian 15.3%; Americas 14.2%; Ashkenazi 15.3%; Finnish 13.7%; Middle Eastern 25.7%; Amish 9.3%.
Estimated AA genotype frequency.
Global 47.3%; European 47.7%; African 48.1%; East Asian 36.4%; South Asian 47.6%; Americas 47.0%; Ashkenazi 47.6%; Finnish 46.7%; Middle Eastern 50.0%; Amish 42.4%.
Estimated AG genotype frequency.
Global 32.3%; European 36.9%; African 16.2%; East Asian 57.8%; South Asian 37.0%; Americas 38.8%; Ashkenazi 37.1%; Finnish 39.6%; Middle Eastern 24.3%; Amish 48.4%.
Estimated GG genotype frequency.
Showing effects for G/G genotype
Cardiovascular & Metabolic
Lipids & Cholesterol
HDL Cholesterol. Evidence: 10/10. Source: PMID 18193043. Higher HDL.
Apolipoprotein A1. Evidence: 8/10. Source: PMID 32203549. Higher Levels.
Total Cholesterol. Evidence: 10/10. Source: PMID 29507422. Slightly Higher.
Heart Disease
Cardiovascular Risk. Evidence: 6/10. Source: PMID 18193043. Slightly Lower Risk.
Showing effects for A/A genotype
HDL Cholesterol. Evidence: 10/10. Source: PMID 18193043. Lower HDL.
Apolipoprotein A1. Evidence: 8/10. Source: PMID 32203549. Lower Levels.
Total Cholesterol. Evidence: 10/10. Source: PMID 29507422. Slightly Lower.
Cardiovascular Risk. Evidence: 6/10. Source: PMID 18193043. Slightly Higher Risk.
Showing effects for A/G genotype
HDL Cholesterol. Evidence: 10/10. Source: PMID 18193043. Typical HDL.
Apolipoprotein A1. Evidence: 8/10. Source: PMID 32203549. Typical Levels.
Total Cholesterol. Evidence: 10/10. Source: PMID 29507422. Typical.
Cardiovascular Risk. Evidence: 6/10. Source: PMID 18193043. Typical Risk.
What this genotype means for the people who carry it
Sample genotype: GG (Homozygous)
Presence of two G alleles is associated with elevated levels of circulating HDL cholesterol [1]. This effect is driven by regulatory changes near the CETP gene that naturally optimize lipid transport [1] [2]. Higher concentrations of apolipoprotein A1, the primary protein structure of HDL particles, are commonly observed [3]. This genetic profile is also associated with a greater abundance of large, lipid-rich HDL subfractions, which are highly efficient at clearing cholesterol from blood vessels [4]. Long-term observational studies suggest that these elevated HDL levels correlate with a reduced risk of coronary artery disease and myocardial infarction [1] [5]. While total cholesterol may be slightly higher, the overall lipid balance remains highly favorable for cardiovascular health [2]. Regular physical activity and a balanced diet can further enhance these natural cardiovascular benefits [6].
Higher HDL cholesterol levels; Slightly lower cardiovascular risk; Higher apolipoprotein A1 levels.
Sample genotype: AA (Homozygous)
Presence of two A alleles is associated with reduced levels of circulating HDL cholesterol [1]. This genetic baseline is driven by regulatory variations near the CETP gene that accelerate the clearance of HDL particles [1] [2]. Lower concentrations of apolipoprotein A1, which can limit the formation of protective HDL, are typical [3]. Additionally, this profile is linked to fewer large, lipid-clearing HDL subfractions in the bloodstream [4]. Because of these lipid transport dynamics, this genotype is associated with a slightly higher risk of coronary artery disease and myocardial infarction [1] [5]. Lifestyle factors such as regular aerobic exercise and a diet rich in healthy fats can help support and raise HDL levels [6]. Routine monitoring of lipid levels can help guide personalized cardiovascular wellness strategies [2].
Lower HDL cholesterol levels; Slightly higher cardiovascular risk; Lower apolipoprotein A1 levels.
Sample genotype: AG (Heterozygous)
Possession of one copy of each allele results in intermediate CETP activity and typical lipid levels [1]. HDL cholesterol concentrations and apolipoprotein A1 levels generally fall within the average range for the population [1] [2]. The balance of large and small HDL subfractions remains typical, providing standard support for reverse cholesterol transport [3]. Because this genotype represents a balanced genetic influence, it does not significantly raise or lower cardiovascular risk on its own [4]. Maintaining a heart-healthy diet and regular exercise can help optimize lipid profiles regardless of genetic baseline [5]. Overall, this genotype provides a typical foundation for cardiovascular health and lipid metabolism [1]. Standard cardiovascular screening and routine lipid panels are sufficient for monitoring [2].
Typical HDL cholesterol levels; Average cardiovascular risk; Typical apolipoprotein A1 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
A large electronic-health-record-based genome-wide study of serum lipids.
Genetic variants influencing circulating lipid levels and risk of coronary artery disease.
Content updated August 2026.
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