The overall goal of this Unit is the application of basic research discoveries to the treatment of genetic diseases, focusing on primary immunodeficiencies and metabolic diseases. This Pediatric Clinical Research Unit (PCRU) was established through a dedicated grant of the Fondazione Telethon to the San Raffaele Telethon Institute for Gene Therapy (HSR-TIGET). The Unit is led by Prof Maria Grazia Roncarolo and operates at HSR-TIGET, and at the Divisions of Hematology, Pediatrics and Neurology, through dedicated medical personnel and trained nursing and technical staff. It provides a suitable environment to translate the results from basic and clinical research into clinical practice and viceversa. Patients with primary immunodeficiencies are seen first at our “Pediatric Immunology” clinic of the San Raffaele Hospital. Children affected by primary immunodeficiencies are offered advanced diagnostic tests, immunological follow-up and adequate therapies.