FXN, or frataxin, is a protein that plays a crucial role in the mitochondria, the energy-producing structures within cells. It is essential for iron metabolism and helps protect cells from oxidative stress. A deficiency in frataxin can lead to various health issues, including Friedreich's ataxia, a genetic disorder that affects movement and coordination. The gene responsible for producing frataxin is located on chromosome 9. Mutations in this gene can disrupt the normal function of frataxin, leading to the accumulation of iron and increased oxidative damage in cells. Research continues to explore potential therapies to address the effects of frataxin deficiency.