Abstract
Patients with inherited bone marrow failure syndromes (IBMFS) have 'stress erythropoiesis', with anaemia, macrocytosis, increased fetal haemoglobin (Hb F) and high erythropoietin levels. In haemoglobinopathies, Hb F levels are regulated by 3 quantitative trait loci, HBS1L-MYB, BCL11A and Xmn1-HBG2. In our study of 97 patients with an IBMFS, increased Hb F was associated with young age, male gender, anaemia, high erythropoietin levels, and alternative alleles in Xmn1-HBG2 [adjusted P = 0·04 for the total group, driven by Fanconi anaemia (P = 0·02) and dyskeratosis congenita (P = 0·09)]. Thus Hb F is regulated in IBMFS by Xmn1-HBG2, as it is in the haemoglobinopathies.