What you carry at this position in your DNA and what research says about it.
Heart and Joint Health: 5/10 evidence, 49 publications.
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Sample genotype (not yours): C/C
Typical Heart and Joint Risk
This genotype is associated with standard levels of COX-2 enzyme activity and typical baseline inflammation. You have a typical risk profile for cardiovascular issues and joint osteoarthritis.
What this genotype means: Typical baseline inflammatory response; Standard risk of osteoarthritis; Typical pain relief from ibuprofen.
Sample genotype (not yours): C/G
Lower Heart and Joint Risk
Carrying one copy of the G allele is linked to reduced COX-2 promoter activity and lower baseline inflammation. This provides moderate protection against cardiovascular events and osteoarthritis.
What this genotype means: Reduced baseline inflammatory markers; Lower risk of severe joint osteoarthritis; Slightly enhanced pain relief from ibuprofen.
Sample genotype (not yours): G/G
Lower Heart Risk but Higher Diabetes Risk
Two copies of the G allele significantly lower COX-2 enzyme activity, reducing cardiovascular and joint risks. However, this genotype is associated with an increased susceptibility to Type 2 diabetes.
What this genotype means: Significantly lower baseline inflammatory response; Lower risk of cardiovascular events and osteoarthritis; Higher risk of Type 2 diabetes.
Gene function and biological role
Gene Function: The PTGS2 gene encodes cyclooxygenase-2, commonly known as COX-2, which is a key enzyme responsible for converting arachidonic acid into prostaglandins. These prostaglandins act as major chemical messengers that drive pain, fever, and inflammatory responses throughout the body. While the related COX-1 enzyme is constantly active to maintain basic cellular functions, COX-2 is highly inducible and spikes rapidly in response to injury or immune triggers. Consequently, genetic variations that alter how much COX-2 is produced can significantly shape an individual's baseline inflammatory tone and long-term susceptibility to inflammatory diseases.
Variant Impact: The rs20417 variant is located in the promoter region of the PTGS2 gene, where it directly regulates how efficiently the gene is transcribed into the COX-2 enzyme. The G allele disrupts a key transcription factor binding site, which reduces promoter activity by approximately 30 percent. This reduction leads to lower overall COX-2 expression and a dampened inflammatory response during immune activation. Conversely, the common C allele maintains standard promoter activity, resulting in typical levels of COX-2 and standard inflammatory signaling.
Key Insight: A genetic variant that lowers your body's inflammatory response can protect your joints and blood vessels, but it may simultaneously increase your risk of metabolic issues like Type 2 diabetes.
Location: PTGS2. Chromosome 1 · 1q31.1 · 186.7 Mb
Estimated prevalence by population
Global 64.5%; European 70.9%; African 44.4%; East Asian 91.2%; South Asian 69.8%; Americas 67.1%; Ashkenazi 58.7%; Finnish 83.4%; Middle Eastern 60.4%; Amish 84.4%.
Estimated CC genotype frequency.
Global 30.7%; European 26.6%; African 44.5%; East Asian 8.6%; South Asian 27.5%; Americas 29.6%; Ashkenazi 35.8%; Finnish 15.8%; Middle Eastern 34.6%; Amish 14.9%.
Estimated CG genotype frequency.
Global 4.8%; European 2.5%; African 11.1%; East Asian 0.2%; South Asian 2.7%; Americas 3.3%; Ashkenazi 5.5%; Finnish 0.7%; Middle Eastern 5.0%; Amish 0.7%.
Estimated GG genotype frequency.
Showing effects for C/C genotype
Cardiovascular & Metabolic
Heart Disease
Cardiovascular Events. Evidence: 5/10. Source: PMID 25957909. Typical Risk.
Diabetes & Glycemic Traits
Type 2 Diabetes. Evidence: 3/10. Source: PMID 12920574. Lower Risk.
Organ Systems
Bone, Joint & Connective Tissue Health
Osteoarthritis. Evidence: 3/10. Source: PMID 20378913. Typical Risk.
Pharmacogenomics
Pain Medication Response
Ibuprofen Response. Evidence: 5/10. Source: PMID 16678543. Typical Response.
Showing effects for C/G genotype
Cardiovascular Events. Evidence: 5/10. Source: PMID 25957909. Lower Risk.
Type 2 Diabetes. Evidence: 3/10. Source: PMID 12920574. Slightly Higher Risk.
Osteoarthritis. Evidence: 3/10. Source: PMID 20378913. Lower Risk.
Ibuprofen Response. Evidence: 5/10. Source: PMID 16678543. Enhanced Relief.
Showing effects for G/G genotype
Type 2 Diabetes. Evidence: 3/10. Source: PMID 12920574. Higher Risk.
What this genotype means for the people who carry it
Sample genotype: CC (Homozygous)
Having the CC genotype means you carry two copies of the major allele, which maintains standard promoter activity for the PTGS2 gene. This results in typical levels of the COX-2 enzyme and standard inflammatory responses. Studies show that this typical activity is associated with standard baseline risks for cardiovascular events, such as stroke and coronary artery disease. It is also linked to a typical risk of developing end-stage osteoarthritis in the hips and knees. However, this genotype is associated with a lower prevalence of Type 2 diabetes compared to those carrying the G allele. When taking NSAIDs like ibuprofen, you are likely to experience a standard, typical level of pain relief.
Typical baseline inflammatory response; Standard risk of osteoarthritis; Typical pain relief from ibuprofen.
Sample genotype: CG (Heterozygous)
Carrying one copy of the G allele reduces the promoter activity of the PTGS2 gene, leading to lower production of the inflammatory COX-2 enzyme. This reduction in enzyme levels is associated with a lower baseline inflammatory response. Clinical research indicates that this genotype offers moderate protection against ischemic stroke and white matter disease. It is also associated with a significantly lower risk of developing severe osteoarthritis in major joints. Additionally, individuals with this genotype may experience enhanced pain relief when using the common NSAID ibuprofen. However, there is a slightly increased risk of metabolic conditions like Type 2 diabetes associated with this lower-activity variant.
Reduced baseline inflammatory markers; Lower risk of severe joint osteoarthritis; Slightly enhanced pain relief from ibuprofen.
Sample genotype: GG (Homozygous)
Carrying two copies of the G allele leads to a substantial reduction in PTGS2 promoter activity, resulting in significantly lower levels of the inflammatory COX-2 enzyme. This lower enzyme activity translates to reduced systemic inflammation and a lower risk of cardiovascular diseases, including stroke. It also provides strong protection against the development of severe hip and knee osteoarthritis. Furthermore, this genotype is linked to enhanced pain relief when taking ibuprofen. However, this pronounced reduction in COX-2 activity is associated with a significantly higher prevalence of Type 2 diabetes. This trade-off highlights how reduced inflammation can protect the heart and joints while potentially impacting metabolic health.
Significantly lower baseline inflammatory response; Lower risk of cardiovascular events and osteoarthritis; Higher risk of Type 2 diabetes.
Variants with shared genetic architecture
rs2745557 · PTGS2 Gene · Chr 1 · Inflammation and Disease Risk
rs5275 · PTGS2 Gene · Chr 1 · Cancer and Stroke Risk
rs5277 · PTGS2 Gene · Chr 1 · Pain Sensitivity
Content updated August 2026.
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