Delivering the "Blueprints" or "DNA Repairing Kits" Instead of Drugs in the Treatment of Congenital Hemoglobinopathies

Hemoglobinopathies, such as β-thalassemia and sickle cell disease (SCD), are among the most common congenital diseases in the world, with high mortality and morbidity rates. The most straightforward approach to correct the main culprit in hemoglobinopathies - the imbalance between the amounts of alpha-like globins/betalike globins- will need to target directly the gene structure or their regulatory elements in order to obtain a sustained therapeutic effect. Finding effective methods to deliver the genetic “blueprints” of the correct and functional protein or, even better, the “DNA repairing kit” able to do the job in situ, remains a major challenge, despite the fact that gene therapy is already used in different diseases. Members of several viral families were employed as “Trojan horses” using the virus ability to deliver a modified genetic material inside the cell and to manipulate the host replication machinery to produce the encoded proteins. Recently, non-viral vectors are gaining advantages for genome correction, especially after the exponential development of the genome editing approaches that can provide precise in situ modifications. This review summarizes the recent advances in the viral and non-viral delivery strategies and emphasizes the therapeutic potential of different approaches designed to correct the genetic defects responsible for the most common hemoglobinopathies.