DETECTION OF THE T(2-13) CHROMOSOMAL TRANSLOCATION IN ALVEOLAR RHABDOMYOSARCOMA USING THE REVERSE TRANSCRIPTASE-POLYMERASE CHAIN-REACTION

Rhabdomyosarcoma, a small-, round-cell tumor of skeletal muscle, is th e most common soft tissue sarcoma found in children. A specific and un ique chromosomal translocation, t(2;13)(935;984), has been described c ytogenetically in a subset of these tumors and is most often associate d with the alveolar histologic subtype. The cloning and sequencing of complementary DNA from fusion transcripts expressed by both cell lines and tumors have shown that this chromosomal translocation results in the fusion of the PAX3 gene on chromosome 2 with a member of the forkh ead gene family, FKHR, on chromosome 13. To detect this genetic abnorm ality we have developed a sensitive method which relies on a reverse t ranscriptase-polymerase chain reaction with primers designed to be spe cific for the chromosome 2 and chromosome 13 sides of the translocatio n. The utility of this approach was tested by analyzing a series of rh abdomyosarcoma cell lines and tumor samples. The data demonstrate that the transcripts derived from the t(2;13) were restricted to tumors ha ving features of the alveolar subtype and that they could be detected with greater ease and sensitivity than with cytogenetic analysis. This approach will facilitate a large-scale group effort to determine the frequency as well as the prognostic and diagnostic significance of thi s chromosomal rearrangement. (C) 1996 Wiley-Liss, Inc.