Primary osteomyelofibrosis and an XX-male genotype.

A 62-yr-old man with two healthy daughters was diagnosed with osteomyelofibrosis. To our surprise, a female XX-karyotype was observed in bone marrow and confirmed in PHA-stimulated T-lymphocytes from peripheral blood. Further molecular genetic investigation revealed a submicroscopic translocation between the short arm of X and Y, which leads to an XX-male genotype based on an unbalanced translocation X;Y. This rare coincidence was further accentuated as the USP9Y gene, suspected to be to be involved in sperm cell production, was absent, but no azoospermia was present. In general, routine cytogenetics may result in findings that need to be further delineated and, as here, lead to a rare observation.