A novel Krüppel-associated box containing the SSX gene (SSX3) on the human X chromosome is not implicated in t(X;18)-positive synovial sarcomas

摘要

The human synovial sarcoma-specific transloca-tion t(X;18) results in the fusion of the SYT gene on chromosome 18 with either one of the Krüppel-associated box (KRAB) containing SSX1 or SSX2 genes on the X chromosome, depending on the exact location of the breakpoint within band Xp11.2. Screening of a testis cDNA library yielded several SSX-positive clones. Subsequent sequence analysis revealed that one third of these clones represent an SSX gene that differs from both SSX 1 and SSX2. This novel member of the family of KRAB containing SSX genes, which we designated SSX3, is 90 % homologous to SSX 1 and 95 % homologous to SSX2 at the cDNA level. Somatic ce11 hybrid analysis indicated that SSX3 maps within Xp11.2→p11.1, the region that also harbors the SSX1 and SSX2 genes. However, we conclude from our RT-PCR data and from results reported in the literature that SSX3 does not act as a fusion partner to SYT in any of the 44 independent synovial sarcomas thus far test