Decreased Hb levels can lead to inadequate oxygen supply, particularly in already damaged blood vessels, which can exacerbate vascular damage and inflammatory responses, thus increasing the risk of cardiovascular events and lower limb arterial disease, Additionally, Hb is an important indicator for diagnosing anemia, and anemia can also impact diabetes control and the progression of complications (52). The gene discussed is GSTM1; the disease is anemia (phenotype).