As shown in Table S2, the HbA2 level was very similar in the non‐α‐thalassemia group (N = 80) and in the α‐thalassemia children with two and three functional α‐genes (N = 33) while the HbA2 level in the two children with only one functional α‐gene was very low. Here, HBA2 is linked to alpha thalassemia spectrum.