PMS2 deficiency refers to a condition where the PMS2 gene, which normally helps prevent cancers, has a mutation causing it to function improperly. This means the gene no longer works as effectively as it should in its role of repairing DNA and preventing uncontrolled cell growth.
Here's a breakdown:
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The Role of PMS2: The PMS2 gene is a crucial part of the mismatch repair (MMR) system within cells. This system acts as a proofreader for DNA, correcting errors that occur during cell division.
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What Happens with a Deficiency: When the PMS2 gene is mutated and deficient, the MMR system is compromised. This leads to a build-up of DNA errors, which can increase the risk of developing certain cancers.
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Increased Cancer Risk: A PMS2 deficiency does not guarantee the development of cancer. However, it significantly increases the risk for several types of cancer, particularly:
- Colorectal cancer
- Endometrial cancer
- Ovarian cancer
- Other cancers associated with Lynch syndrome (also known as hereditary non-polyposis colorectal cancer or HNPCC)
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Inheritance: PMS2 deficiency is often inherited, meaning it's passed down from parents to their children. Genetic testing can determine if someone carries a mutated PMS2 gene.
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Management: Individuals with PMS2 deficiency require increased surveillance and may consider preventative measures to reduce their cancer risk. This includes regular screenings (colonoscopies, endometrial biopsies, etc.) and, in some cases, prophylactic surgery. Genetic counseling is also recommended.
In summary, PMS2 deficiency results from a mutation in the PMS2 gene, impairing its ability to repair DNA and increasing the risk of developing certain cancers, particularly those associated with Lynch syndrome. Early detection and proactive management are critical for individuals with this condition.
