ABO and cystic fibrosis: The specific and precise incorporation of this c.261delG polymorphism within the ABO gene has been attempted in the present work aiming to reproduce the genetic basis naturally associated to blood type O. Exploiting the CRISPR/Cas9‐targeted integration to correct genetic defects has led to a number of proof‐of‐principle works in patient‐derived hiPSCs, in which the mutations responsible for cystic fibrosis, haemophilia A and β‐thalassemia were successfully corrected, although with a limited efficiency.36, 37, 38