The JAK2 mutation refers to a genetic alteration in the JAK2 gene, which plays a crucial role in blood cell production. This mutation is commonly associated with various blood disorders, particularly myeloproliferative neoplasms (MPNs), where the body produces too many blood cells. Individuals with the JAK2 mutation may experience symptoms such as fatigue, headaches, and an increased risk of blood clots. Testing for this mutation can help diagnose conditions like polycythemia vera and essential thrombocythemia, allowing for more targeted treatment options.