HBA2 and thalassemia: Over 380 variants involving the α-globin genes (HBA1, HBA2) and wider clusters have been associated with α-thalassemia to date (see the Ithanet database at https://www.ithanet.eu (accessed on 24 January 2024) and the HbVar database at http://globin.cse.psu.edu (accessed on 24 January 2024)).