A newly‐characterized α‐thalassaemia‐1 deletion removes the entire α‐like globin gene cluster in an Italian family

Summary We describe a new deletional form of α thalassae‐mia which encompasses the entire α‐like globin gene cluster in a 15‐year‐old boy of Southern Italian descent. The deletion removes ∼31 kb, the 5′‐end point is located approximately 4 kb upstream of the ζ gene, while the 3′‐end point maps between the α₁‐ and θ₁‐globin genes. The interaction of this deletion with the common ‐α^3.7 form gives origin to a classical form of haemoglobin (Hb) H disease in the propositus of this study. Deletional forms of ζα‐thalassaemia are uncommon in the Mediterranean basin; as for other unusual ζα‐thalassae‐mia forms, heterozygotes for this mutation may escape detection in population surveys based on ζ and α probes.