Hemoglobin A2 (HbA2) levels >3.5% are indicators of β-thalassemia and <2.5% of α-thalassemia.10,11 Interestingly, recent studies have reported that HbA2 levels were also linked to pregnancy, geographic region, race, as well as detection method.12-14 However, the levels of HbA2 and fetal hemoglobin (HbF) in the population of child-bearing age have not been determined for Chongqing, China. The gene discussed is HBA2; the disease is thalassemia.