Thalassemias are part of the group of hereditary diseases called haemoglobinopathies and are characterised by chronic anaemia, varying in severity, resulting from a quantitative defect in haemoglobin production. In the Mediterranean region, two forms of haemoglobinopathies are frequent: beta Thalassemia and sickle cell anaemia (or drepanocytosis), both highly invalidating, with a frequency of carriers varying from 1 to 15%. Again, these are recessive diseases which, if both partners in the couple are carriers, can be passed on to their children. It is possible to detect possible carriers through a series of biochemical tests (blood count, HbA2 dosage, HbF dosage, ferritin test, etc.). Only in case of doubt can we proceed with genetic testing to search for mutations in the genes that encode haemoglobin.