Delineation of a 150-kb breakpoint cluster in benign thyroid tumors with 19q13.4 aberrations

Structural rearrangements involving the long arm of chromosome 19 character ize a cytogenetic subgroup of benign thyroid tumors and constitute one of t he most frequent specific chromosome abnormalities in epithelial tumors. Re cently. we have been able to narrow down the breakpoint region affected in two cell lines to a region covered by a single PAC clone. Close to that reg ion a candidate gene has been identified which we tentatively referred to a s RITA (Rearranged In Thyroid Adenomas) now named ZNF331 according to HUGO nomenclature. However, the results had been obtained on two cell lines only making it necessary to extend the studies to a larger number of tumors inc luding primary material. Herein, we have used four further primary tumors s howing translocations involving 19q13 for fluorescence in situ hybridizatio n (FISH) mapping studies using a variety of molecular probes from a 470-kbp cosmid/BAC contig. Ten new STSs were characterized and physically mapped w ithin an EcoRI restriction map. The results enabled us to define an approxi mately 150-kbp breakpoint cluster region of the 19q13 aberrations in benign thyroid tumors flanked by two newly established STS markers. Copyright (C) 2001 S. Karger AG, Basel.