Considering Igs formulation a higher concentration of IgA, anti-Rh and anti-RhD increase the prevalence of adverse reactions (50), on the other side some authors reported a greater risk of side effects in patients with primary antibody defects particularly in those with low IgA levels (51), attention should be paid also in patients with a previous history of allergies and thrombotic events. The gene discussed is CD79A; the disease is Allergy.