ACSS2 and thalassemia: The subtypes of α-thalassemia that we analysed in this study were --SEA, -α3.7, -α4.2, αCSα, αWSα and αQSα, and their gene frequency was 2.54% (95%CI: 1.57~3.51), 1.59% (95%CI: 0.93~2.24), 0.54% (95%CI: 0.31~0.78), 0.24% (95%CI: 0.16~0.32), 0.26% (95%CI: 0.17~0.36) and 0.06% (95%CI: 0.02~0.10), respectively (Fig. 5, Table 2).