“…Later, SCID due to a defect of the common gamma chain (gC) gene was also treated. Both deficiencies are due to autosomal recessive gene defects, leading to severe combined immunodeficiency diseases (ADA-SCID, SCID-X1) (Blaese et al, 1995;Cavazzana-Calvo et al, 2000;Fischer et al, 2002). In the recent ADA-SCID study carried out in Italy (Auti et al, 2002), patients treated with genemodified autologous haemaotopoietic stem cells gained clinical benefit.…”