Chromosome abnormalities in bone marrow of Fanconi anemia patients.

We report the clonal chromosome abnormalities of five patients with Fanconi anemia (FA). In one with myelodysplastic syndrome (MDS), an abnormal clone was present in the bone marrow (BM): 47,XY,trp(1)(q32q44), + mar. Two had acute myeloblastic leukemia (AML), one with monosomy 7 and the other with 46,XY,add(1)(p34),del(7)(p13). In the two others without signs of MDS or AML, pseudodiploidy with 46,XX,-5, +8 and 46,XX, +5, -21 were present, respectively. The significance of these abnormalities is discussed.