The first de novo heterozygous missense mutation in the IKZF1 gene was described by Goldman et al. in 2012, in a 33-week preterm infant with pancytopenia and loss of B cells, which shared phenotypic similarities with the IKZF1-null mouse animal model and that affected the ZF4 domain of IKAROS [15]. Here, IKZF1 is linked to Pancytopenia.