HBA2 and thalassemia: Of the pathogenic variants, two duplication CNVs are associated with β-thalassaemia (CD 62–83 (+65 bp), IthaID: 2190; >29.5 kb duplication, IthaID: 3869), while five CNVs are associated with α-thalassaemia caused by a fusion of HBA1-HBA2.