Molecular scissors

In medicine there are some events that have marked history and that those who have some interest in the field certainly remember as fundamental moments of change and turning point. In 1982, the first drug produced in genetically modified bacteria was approved; from that moment on, those suffering from diabetes have the possibility of receiving a recombinant insulin, rather than that derived from animals or cadavers, with the great advantage of reducing risks and side effects and having larger quantities of the drug available, in a timely manner. Shorter. In 2000, the first sequence of the human genome was published, opening up the possibility of discovering and investigating the mechanisms underlying the evolution of the human genome and its regulation. In 2020, the first vaccine based on RNA technology was approved to defend us from Covid infections.

A new date to mark in the medical history book is 2023, for the approval by the United Kingdom of the first therapy that uses "molecular scissors" to correct DNA. This technology has been used in research for over 10 years, which in specific terms is called CRISPR and whose importance was underlined by the awarding of the Nobel Prize to the two researchers who invented this "DNA correction" system. On 16 November 2023, the competent authority for medicine regulation in Great Britain expressed a favorable opinion for the use of this technology for therapeutic purposes. The treatment is indicated for sickle cell anemia and beta-thalassemia, two very disabling pathologies, both for the symptoms they cause and for the need to receive frequent blood transfusions.

Both diseases are due to mutations in the gene that encodes the production of hemoglobin, a protein present in red blood cells with the function of transporting oxygen in the blood. In different ways, both pathologies cause an insufficient supply of oxygen to the tissues, resulting in chronic fatigue, breathing difficulties, developmental problems and very severe pain.

With "molecular scissors" it was possible to instruct the cells of the bone marrow to produce fetal hemoglobin, which does not have the defect of adult hemoglobin. In this way red blood cells can correctly transport oxygen throughout the body.

The clinical studies that led to the approval of this type of therapy involved 29 patients with sickle cell anemia and 42 with beta-thalassemia. During one year of observation, 28 patients in the first group no longer had the pain attacks characteristic of the diseases, 39 patients in the second group did not need to receive transfusions, with few side effects related to the therapy.

Certainly one of the big limitations concerns the very high costs. It is hoped that with the progress of technology and the greater diffusion of treatments, greater economic accessibility will be achieved. A new era is certainly opening up, characterized by targeted interventions at the genetic level. Alongside the surgical scalpels we can insert "molecular scissors": two different precision instruments, both ready to treat.

Valentina Turinetto

NP Dicembre 2023