According to Bolton PF et al. (2001) and Depienne C et al. (2009) the patients with duplication of the critical region (BP2-BP3), as occurs in these two cases, have frequently an abnormal phenotype that includes development delay, especially in speech and language, different degrees of intellectual disability, motor coordination difficulties and mild dysmorphisms (which are absent in our cases) [34, 40]. Here, IGFBP2 is linked to Intellectual disability.