What you carry at this position in your DNA and what research says about it.
Fatty Acid Metabolism: 8/10 evidence, 17 publications.
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Sample genotype (not yours): C/C
Efficient Omega Conversion with Higher Cholesterol Risk
Rapidly converts plant-based fats into active omega fatty acids, but is associated with higher cholesterol and glucose levels.
What this genotype means: Efficient synthesis of EPA and DHA; Higher total and LDL cholesterol; Slightly elevated blood glucose.
Sample genotype (not yours): A/A
Slower Omega Conversion with Favorable Cholesterol Levels
Slower conversion of plant-based fats to active omega lipids, paired with lower cholesterol and glucose levels.
What this genotype means: Slower synthesis of EPA and DHA; Lower total and LDL cholesterol; Slightly higher bipolar disorder susceptibility.
Sample genotype (not yours): C/A
Balanced Fatty Acid Conversion and Typical Lipid Profile
Maintains a balanced rate of omega fatty acid conversion with intermediate cholesterol and metabolic risks.
What this genotype means: Moderate fatty acid conversion rate; Typical baseline cholesterol levels; Average metabolic and inflammatory risk.
Gene function and biological role
Gene Function: The FADS2 gene encodes fatty acid desaturase 2, a rate-limiting enzyme crucial for lipid metabolism. This enzyme catalyzes the rate-limiting step in converting short-chain dietary plant fats into long-chain polyunsaturated fatty acids. Specifically, it converts alpha-linolenic acid into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and linoleic acid into arachidonic acid. These end-product fatty acids are essential components of cellular membranes, especially in the brain and cardiovascular system. Variations in this gene directly alter enzyme activity, shifting the balance between precursor fats and highly active long-chain lipids.
Variant Impact: The rs174576 variant is an intronic change within the FADS2 gene that acts as a major regulator of desaturase enzyme expression. Carrying the common C allele increases enzyme activity, leading to rapid conversion of plant-derived oils into highly active long-chain fatty acids. Conversely, the minor A allele reduces enzyme efficiency, resulting in a buildup of precursor fats and lower levels of converted products like arachidonic acid. This metabolic shift influences systemic inflammation, lipid profiles, and cellular membrane composition throughout the body. Because of these broad physiological effects, the variant is linked to differences in cholesterol levels, blood glucose, and neuropsychiatric susceptibility.
Key Insight: Slower converters of plant-based omega fats may need direct marine-sourced EPA and DHA because their bodies cannot efficiently synthesize them from vegetable oils.
Location: FADS2. Chromosome 11 · 11q12.2 · 61.8 Mb
Estimated prevalence by population
Global 43.1%; European 43.1%; African 52.4%; East Asian 19.8%; South Asian 66.6%; Americas 23.2%; Ashkenazi 48.9%; Finnish 33.5%; Middle Eastern 36.2%; Amish 55.0%.
Estimated CC genotype frequency.
Global 44.0%; European 45.1%; African 40.0%; East Asian 49.4%; South Asian 30.0%; Americas 49.9%; Ashkenazi 42.1%; Finnish 48.8%; Middle Eastern 47.9%; Amish 38.3%.
Estimated CA genotype frequency.
Global 12.9%; European 11.8%; African 7.6%; East Asian 30.8%; South Asian 3.4%; Americas 26.8%; Ashkenazi 9.1%; Finnish 17.8%; Middle Eastern 15.8%; Amish 6.7%.
Estimated AA genotype frequency.
Showing effects for C/C genotype
Nutrition & Metabolism
Macronutrient Metabolism
Fatty Acid Conversion. Evidence: 4/10. Source: PMID 31991592. Highly Efficient.
Cardiovascular & Metabolic
Lipids & Cholesterol
Cholesterol Levels. Evidence: 8/10. Source: PMID 35213538. Higher Cholesterol.
Diabetes & Glycemic Traits
Blood Glucose. Evidence: 6/10. Source: PMID 41044249. Higher Glucose.
Cancer & Oncology
Colorectal Cancer
Colorectal Cancer. Evidence: 6/10. Source: PMID 38872215. Increased Risk.
Neurology & Mental Health
Mood Disorders
Bipolar Disorder. Evidence: 5/10. Source: PMID 28115744. Lower Risk.
Showing effects for A/A genotype
Fatty Acid Conversion. Evidence: 4/10. Source: PMID 31991592. Slower Conversion.
Cholesterol Levels. Evidence: 8/10. Source: PMID 35213538. Lower Cholesterol.
Blood Glucose. Evidence: 6/10. Source: PMID 41044249. Lower Glucose.
Colorectal Cancer. Evidence: 6/10. Source: PMID 38872215. Decreased Risk.
Bipolar Disorder. Evidence: 5/10. Source: PMID 28115744. Slightly Higher Risk.
Showing effects for C/A genotype
Fatty Acid Conversion. Evidence: 4/10. Source: PMID 31991592. Moderate.
Cholesterol Levels. Evidence: 8/10. Source: PMID 35213538. Typical Levels.
Blood Glucose. Evidence: 6/10. Source: PMID 41044249. Typical Glucose.
Colorectal Cancer. Evidence: 6/10. Source: PMID 38872215. Typical Risk.
Bipolar Disorder. Evidence: 5/10. Source: PMID 28115744. Typical Risk.
What this genotype means for the people who carry it
Sample genotype: CC (Homozygous)
Highly active desaturase enzymes ensure efficient synthesis of long-chain polyunsaturated fatty acids from dietary plant oils. However, this rapid conversion also generates higher levels of arachidonic acid, which can promote inflammatory pathways when dietary omega-6 intake is high. Large-scale genetic studies associate this genotype with elevated total cholesterol, LDL cholesterol, and blood glucose levels. There is also a moderately increased risk of colorectal cancer linked to this high-activity profile. On the positive side, efficient fatty acid synthesis in the brain appears protective, correlating with a lower risk of developing bipolar disorder. Balancing dietary fat intake by reducing refined seed oils and emphasizing anti-inflammatory omega-3s can help manage these metabolic risks.
Efficient synthesis of EPA and DHA; Higher total and LDL cholesterol; Slightly elevated blood glucose.
Sample genotype: AA (Homozygous)
Reduced desaturase enzyme activity leads to slower conversion of short-chain plant oils into active long-chain fatty acids. This slower processing results in lower levels of arachidonic acid, which can help limit systemic inflammatory responses. This metabolic pattern is strongly associated with favorable lipid profiles, including lower total cholesterol, lower LDL cholesterol, and lower blood glucose. Additionally, a reduced risk of colorectal cancer is observed with this genotype. However, because the body is less efficient at synthesizing long-chain omega-3s like EPA and DHA from plant precursors, there is a greater reliance on direct dietary sources. This reduced synthesis in the brain may also contribute to a slightly higher susceptibility to bipolar disorder. Consuming pre-formed omega-3s from marine sources can help bypass this conversion bottleneck.
Slower synthesis of EPA and DHA; Lower total and LDL cholesterol; Slightly higher bipolar disorder susceptibility.
Sample genotype: CA (Heterozygous)
An intermediate rate of fatty acid desaturation provides a balanced metabolic profile. Precursor plant fats are converted to active long-chain lipids at a moderate pace, preventing extreme shifts in systemic inflammation. Cholesterol markers, including LDL and total cholesterol, generally remain at typical baseline levels. Similarly, blood glucose levels and colorectal cancer risks do not show the elevations seen in the high-activity genotype. Bipolar disorder susceptibility is also close to the population average. This balanced state offers flexibility, though maintaining a healthy ratio of dietary omega-3 to omega-6 fats remains beneficial for overall cardiovascular and cellular health.
Moderate fatty acid conversion rate; Typical baseline cholesterol levels; Average metabolic and inflammatory risk.
Variants with shared genetic architecture
rs174570 · FADS2 Gene · Chr 11 · Fatty Acid Metabolism
rs174574 · FADS2 Gene · Chr 11 · Fatty Acid Metabolism
rs99780 · FADS2 Gene · Chr 11 · Omega-3 Metabolism
Content updated August 2026.
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