The current criterion for the diagnosis of anemia is Hb below 12 g/dL for women and 13 g/dL for men.[5] However, since this parameter is concentration-based and is known to be influenced by altitude exposure, the criteria for diagnosing anemia and polycythemia should be reevaluated in the case of high-altitude residency. This evidence concerns the gene GSTM1 and polycythemia.