Translocation (12;22)(p13;q12) as sole karyotypic abnormality in a patient with nonlymphocytic leukemia

Cytogenetic analysis of unstimulated bone marrow (BM) and peripheral blood (PB) cells of a patient with clinical features of atypical chronic myeloid leukemia (CML) showed t(12;22)(p13;q12) as the sole karyotypic abnormality. Subsequent fluorescence in situ hybridization (FISH) with abl- and bcr-specific cosmids as well as chromosome 12- and 22-specific DNA libraries and Southern blot analysis confirmed that in this patient t(12;22) does not constitute a cryptic Ph variant. Recently, a few very similar cases were reported by other investigations. The possible significance of this translocation as a new cytogenetic marker for nonlymphocytic leukemia is discussed.