MOLECULAR CHARACTERIZATION OF THE T(8-13)(P11-Q12) TRANSLOCATION ASSOCIATED WITH AN ATYPICAL MYELOPROLIFERATIVE DISORDER - EVIDENCE FOR 3 DISCRETE LOCI INVOLVED IN MYELOID LEUKEMIAS ON 8P11

A reciprocal chromosome translocation between 13q12 and 8p11 is the co nsistent cytogenetic abnormality seen in a nonspecific myeloproliferat ive disorder that is associated with T-cell leukemia/lymphoma and peri pheral blood eosinophilia. Detailed molecular analyses of the transloc ation breakpoints associated with this rearrangement have not been rep orted to date, We have now generated somatic cell hybrids from a newly described patient with this specific structural rearrangement and ana lyzed the breakpoints on the derivative chromosomes, We have shown tha t the breakpoint on chromosome 13 lies within a 300- to 500-kb region defined by the KIAA177 gene and D13S1123 marker, In addition, we have identified a 1.2-Mb YAC, 959A4, that crosses the translocation breakpo int on the short arm of chromosome 8 in this patient. The location of this breakpoint in 8p11 is distinct from the t(8;16) and t(8;22) trans locations associated with M4/M5 myeloid leukemias, and suggests that t hree distinct loci located within 8p11 are involved in the pathogenesi s of myeloid neoplasias. (C) 1997 by The American Society of Hematolog y.