De novo TP53 germline activating mutations in two patients with the phenotype mimicking Diamond-Blackfan anemia

Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome, associated with mutations in ribosomal protein (RP) genes. Growing data on mutations in non-RP genes in patients with DBA-like phenotype became available over recent years. We describe two patients with the phenotype of DBA (onset of macrocytic anemia within the first year of life, paucity of erythroid precursors in bone marrow) and germline de novo variants in the TP53 gene. Both patients became transfusion independent, probably due to L-leucine therapy. The possible role of TP53 variants should be considered in patients with DBA-like phenotype and no mutations in RP genes.