REGIONAL FINE MAPPING OF THE MULTIPLE-ABERRATION REGION INVOLVED IN UTERINE LEIOMYOMA, LIPOMA, AND PLEOMORPHIC ADENOMA OF THE SALIVARY-GLAND TO 12Q15

Cytogenetic aberrations involving 12q13-15 are frequently observed in a variety of benign solid tumors. Using a chromosome walking approach combined with fluorescence in situ hybridization analysis, we were abl e to show that the chromosome 12 breakpoints involved in uterine leiom yoma, pleomorphic adenoma of the salivary gland, and lipoma cluster to the same chromosomal region, which we therefore designated MAR (multi ple-aberration region). By comparing the G-banding pattern of prometap hase chromosomes of amniotic fluid cells and lymphocytes to the positi on of hybridization signals obtained with a cosmid pool encompassing t his breakpoint hot spot region, MAR was assigned to 12q15. We conclude that, despite the cytogenetic breakpoint assignment to the three band s 12q13-15 in individual uterine leiomyomas, lipomas, and pleomorphic adenomas of the salivary glands in the past, most likely 12q15 is the only 12q breakpoint site in these three distinct solid tumor types. (C ) 1995 Wiley-Liss, Inc.