Acute promyelocytic leukemia (APL) is associated with 2 cardinal features: a granulocytic differentiation block and reciprocal and balanced translocations that always involve rearrangement of the RARA gene (180240). The most frequent translocation is t(15,17)(q21;q22), which fuses the RARA gene with the PML gene (102578) and represents more than 98% of APL (Vitoux et al., 2007).

XLANP is an X-linked recessive hematologic disorder characterized by early-onset anemia and bone marrow erythroid hypoplasia with variable neutropenia. Some patients may have low platelets or platelet abnormalities. The severity is variable. Some patients have shown a favorable response to corticosteroid treatment (summary by Hollanda et al., 2006 and Sankaran et al., 2012). In some cases, the disorder may resemble Diamond-Blackfan anemia (see, e.g., DBA1; 105650) (Sankaran et al., 2012; Parrella et al., 2014; Klar et al., 2014).