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Disclaimer: This article is for informational purposes only and is not intended to diagnose any conditions. LifeDNA does not provide diagnostic services for any conditions mentioned in this or any other article.
The CAT gene, which encodes the enzyme called catalase, is crucial in the body’s defense against oxidative stress. As part of the antioxidant enzyme system, catalase protects cells from damage by reactive oxygen species (ROS), particularly hydrogen peroxide (H₂O₂). Its activity is essential for maintaining redox balance, supporting cellular detoxification, and reducing the risk of chronic diseases associated with oxidative damage.
Detoxification in the body refers to the natural, biological process through which the body neutralizes, transforms, and eliminates harmful substances. Harmful substances can be produced internally (like metabolic waste or reactive oxygen species) or introduced from the outside (like pollutants, alcohol, medications, and toxins).
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In essence, detoxification is a constant and critical process that keeps the body functioning efficiently and protects it from internal and environmental harm. While the term “detox” is often misused in marketing, in scientific terms, it refers to a complex and essential physiological function.
The CAT gene, found on chromosome 11, produces the catalase enzyme. The catalase enzyme is a protein that is made up of four identical parts. Each part contains a heme group, which helps break down hydrogen peroxide (Hâ‚‚Oâ‚‚) into water (Hâ‚‚O) and oxygen (Oâ‚‚), a vital process that protects cells from damage.
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2 H₂O₂ → 2 H₂O + O₂
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This prevents hydrogen peroxide, a by-product of normal metabolism, from accumulating to toxic levels. In the absence of sufficient catalase activity, hydrogen peroxide can generate hydroxyl radicals (•OH). Hydroxyl radicals make for some of the most damaging free radicals in biological systems.
Oxidative stress occurs when there is an imbalance between ROS production and the body’s ability to neutralize them. The CAT gene, by coding for catalase, is one of the first lines of defense in this system. Its role is especially critical in detoxifying hydrogen peroxide generated by mitochondrial respiration, peroxisomal β-oxidation of fatty acids, and certain xenobiotic (foreign chemical) metabolism reactions.
Catalase works in concert with other antioxidant enzymes such as:
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Together, these enzymes form a tightly regulated network that detoxifies ROS and protects against oxidative damage to DNA, proteins, and lipids.
Catalase is highly expressed in tissues with elevated oxidative metabolism. This includes the liver, kidneys, lungs, and red blood cells. In the liver, it plays a key role in neutralizing ROS generated during the detoxification of drugs and alcohol. In red blood cells, catalase prevents oxidative damage to hemoglobin and membrane structures.
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Low catalase activity has been implicated in several conditions involving increased oxidative stress, such as:
Polymorphisms in the CAT gene may influence enzyme activity and certain disease susceptibility. One well-studied variant is rs1001179 (C/T in the promoter region), which affects the gene’s expression.
A 2022 paper studied the rs1001179 polymorphism of the CAT gene in chronic lymphocytic leukemia (CLL) cells. Specifically, the T allele of rs1001179 was associated with higher CAT expression compared to the CC genotype. This is because the T allele makes the promoter region of the CAT gene more accessible to transcription factors, enhancing gene expression activity. Additionally, CLL cells with the T allele also show lower DNA methylation, which further increases CAT expression. Together, these findings suggest that rs1001179 affects CAT levels through both genetic and epigenetic mechanisms.
Another 2024 study confirmed that CLL patients with the TT genotype of rs1001179 have higher CAT expression and also experience a shorter time-to-first-treatment, indicating a more aggressive disease course in CLL.
Understanding the role of the CAT gene in detoxification has implications in:
Additionally, catalase mimetics and gene therapy approaches are being explored for diseases linked to excessive oxidative damage.
The CAT gene plays a vital role in the body’s detoxification system by enabling the breakdown of hydrogen peroxide into harmless by-products. Through its regulation of oxidative stress, it helps protect against cellular damage, inflammation, and chronic disease. Genetic differences in catalase expression and activity further shape an individual’s ability to detoxify reactive molecules, making CAT a gene of interest in the fields of preventive health, toxicology, and personalized medicine.
