What you carry at this position in your DNA and what research says about it.
HDL Cholesterol Levels: 10/10 evidence, 18 publications.
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Sample genotype (not yours): C/C
Higher Cardiovascular Risk and Lower HDL
Carrying two copies of the C allele is associated with lower levels of protective HDL cholesterol and higher triglycerides. This combination can unfavorably alter your overall lipid profile.
What this genotype means: Lower circulating HDL cholesterol; Higher blood triglyceride levels; Slightly lower polyunsaturated fatty acids.
Sample genotype (not yours): C/T
Carrying one copy of the C allele is associated with lower levels of protective HDL cholesterol and higher triglycerides. This intermediate profile behaves similarly to the C/C genotype.
Sample genotype (not yours): T/T
Favorable Lipid Profile and Higher HDL
Carrying two copies of the T allele is associated with higher levels of protective HDL cholesterol and lower triglycerides. This genetic profile supports a healthier cardiovascular lipid balance.
What this genotype means: Higher circulating HDL cholesterol; Lower blood triglyceride levels; Higher polyunsaturated fatty acids.
Gene function and biological role
Gene Function: The CETP gene encodes the cholesteryl ester transfer protein, which plays a central role in remodeling circulating lipoproteins [1]. This protein facilitates the transfer of cholesteryl esters from protective high-density lipoproteins (HDL) to pro-atherogenic lipoproteins in exchange for triglycerides [1]. High CETP activity typically results in lower circulating levels of HDL cholesterol and higher levels of low-density lipoprotein (LDL) cholesterol [1]. Consequently, genetic variations in this gene are among the most powerful determinants of blood lipid profiles in humans [2]. Modulating this pathway is a major focus of therapeutic strategies aimed at reducing cardiovascular risk [2].
Variant Impact: The rs183130 variant is a single nucleotide polymorphism located in the promoter region of the CETP gene [1]. This genetic change alters transcription factor binding sites, directly modulating the expression of the CETP protein [1]. The C allele is linked to higher CETP expression, which accelerates the clearance of protective HDL particles from the bloodstream [1]. Conversely, the T allele is associated with lower CETP expression, allowing HDL particles to persist longer and maintain higher concentrations [1]. This promoter variant represents a highly replicated genetic signal influencing lipid and fatty acid levels across diverse global populations [3].
Key Insight: This variant acts like a dimmer switch for the CETP gene, where carrying the T allele naturally lowers gene expression to boost protective HDL cholesterol levels.
Location: CETP. Chromosome 16 · 16q13 · 57.0 Mb
Estimated prevalence by population
Global 50.4%; European 45.8%; African 55.3%; East Asian 69.8%; South Asian 44.1%; Americas 51.0%; Ashkenazi 53.9%; Finnish 52.4%; Middle Eastern 58.6%; Amish 37.2%.
Estimated CC genotype frequency.
Global 41.0%; European 43.8%; African 38.1%; East Asian 27.5%; South Asian 44.6%; Americas 40.8%; Ashkenazi 39.0%; Finnish 40.0%; Middle Eastern 35.9%; Amish 47.6%.
Estimated CT genotype frequency.
Global 8.6%; European 10.5%; African 6.6%; East Asian 2.7%; South Asian 11.3%; Americas 8.2%; Ashkenazi 7.1%; Finnish 7.6%; Middle Eastern 5.5%; Amish 15.2%.
Estimated TT genotype frequency.
Showing effects for C/C genotype
Cardiovascular & Metabolic
Lipids & Cholesterol
HDL Cholesterol. Evidence: 10/10. Source: PMID 38448586. Lower HDL.
Triglycerides. Evidence: 9/10. Source: PMID 38448586. Higher Levels.
Total Cholesterol. Evidence: 10/10. Source: PMID 38448586. Typical Levels.
Nutrition & Metabolism
Macronutrient Metabolism
Omega-3 Fatty Acids. Evidence: 9/10. Source: PMID 41044249. Lower Levels.
Showing effects for C/T genotype
Total Cholesterol. Evidence: 10/10. Source: PMID 38448586. Slightly Higher.
Showing effects for T/T genotype
HDL Cholesterol. Evidence: 10/10. Source: PMID 38448586. Typical HDL.
Triglycerides. Evidence: 9/10. Source: PMID 38448586. Typical Levels.
Omega-3 Fatty Acids. Evidence: 9/10. Source: PMID 41044249. Higher Levels.
What this genotype means for the people who carry it
Sample genotype: CC (Homozygous)
Having the C/C genotype is consistently linked to lower plasma concentrations of high-density lipoprotein (HDL) cholesterol across multiple ethnic groups [1]. This effect is driven by increased activity of the CETP protein, which accelerates the transfer of cholesterol out of protective HDL particles [1]. In addition to lower HDL, this genotype is associated with higher circulating triglycerides and lower levels of beneficial polyunsaturated fatty acids like docosahexaenoic acid (DHA) [2]. While total cholesterol may remain slightly lower, the overall lipid balance is less favorable for cardiovascular health [1]. Maintaining a diet rich in healthy fats and engaging in regular aerobic exercise can help support healthy HDL levels.
Lower circulating HDL cholesterol; Higher blood triglyceride levels; Slightly lower polyunsaturated fatty acids.
Sample genotype: CT (Heterozygous)
Having the C/T genotype means carrying one copy of the C risk allele, which behaves dominantly to lower protective HDL cholesterol levels [1]. The presence of the C allele maintains higher CETP promoter activity, leading to faster clearance of HDL particles from the bloodstream [1]. This genotype is also associated with higher circulating triglycerides and lower levels of beneficial omega-3 and omega-6 polyunsaturated fatty acids [2]. Although total cholesterol levels may be slightly lower than in T/T individuals, the reduction in protective HDL and increase in triglycerides represents a less optimal lipid profile [1]. Standard cardiovascular support strategies, such as a Mediterranean-style diet, are often recommended to optimize lipid ratios.
Sample genotype: TT (Homozygous)
Having the T/T genotype is associated with a highly favorable blood lipid profile characterized by naturally higher levels of protective HDL cholesterol [1]. Because the T allele reduces the expression of the CETP gene, HDL particles remain in circulation longer to perform their protective functions [1]. This genotype is also linked to lower circulating triglycerides and higher levels of beneficial polyunsaturated fatty acids, including docosahexaenoic acid (DHA) [2]. Although total cholesterol levels may be slightly higher due to the increased abundance of HDL particles, the overall ratio of lipids is highly favorable for cardiovascular health [1]. This genetic profile provides a natural advantage in maintaining healthy cholesterol ratios.
Higher circulating HDL cholesterol; Lower blood triglyceride levels; Higher polyunsaturated fatty acids.
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 characterization of circulating metabolic biomarkers.
The power of genetic diversity in genome-wide association studies of lipids.
A genetic map of human metabolism across the allele frequency spectrum.
Content updated August 2026.
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