However, these amino acids are, for example, sufficient to allow H3.3 to interact with specific histone chaperones, such as the Death domain-associated protein (DAXX), the alpha-thalassemia/mental retardation X-linked protein (ATRX) complex, and the histone regulator A (Hira)/calcineurin-binding protein 1 (Cabin 1)/ubinuclein1 (Ubn1) complex, involved in its loading on chromatin [7,38,39,40,41]. The gene discussed is HIRA; the disease is thalassemia.