Bloom syndrome is a genomic instability syndrome associated with predisposi
tion to development of various types of malignancy. In this report, rye des
cribed a 7-year-old boy with Bloom syndrome (BS) and myelodysplastic syndro
me (MDS) associated with monosomy 7 and loss of the Y chromosome. To our kn
owledge, this was the first case with BS showing monosomy 7 and MDS during
the early childhood period. (C) 1999 Elsevier Science Inc., 1999. All right
s reserved.