RUNX1T1 and Splenomegaly: They can be balanced or unbalanced and result in different outcomes, depending on deletion/duplication of genomic material, gene disruption, or position effects.<h4>Case presentation</h4>We report on a patient presenting with severe anemia, splenomegaly, mild intellectual disability and facial dysmorphisms harboring a 4.3 Mb duplication at 1p22.1p21.3 and a 2.1 Mb deletion at 8q21.3q22.1, involving RUNX1T1 gene.