PLCG2 and X-linked agammaglobulinemia: Patient 1 carrying the p.Leu845_Leu848 PLCG2 deletion showed the complete absence of B cells and circulating immunoglobulins, an immune phenotype compatible with a rare form of non-X-linked agammaglobulinemia [16] and quite similar to the immune phenotype of the APLAID patients carrying the missense p.Leu848Pro PLCG2 variant [8, 9].