hREC2, a RAD51-like Gene, is Disrupted by t(12;14)(q15;q24.1) in a Uterine Leiomyoma

A balanced translocation between chromosomes 12 and 14 is commonly seen in uterine leiomyoma (UL). We have previously cloned and characterized a 2 Mb segment of human chromosomal subband 14q24.1, and have shown that the t(12;14)(q15;q24.1) breakpoints from several ULs map within this region. Exon trapping of DNA clones spanning one such breakpoint revealed coding sequences from hREC2, a gene that shows significant amino acid sequence identity to the double-strand break repair enzyme RAD51. We report here that this breakpoint is located within a 19 kb intron of the hREC2 gene and that the translocation results in the premature truncation of the major hREC2 transcript. Mapping and sequence analyses show that alternative transcripts of the hREC2 gene, including novel isoforms identified in testis and uterus, are not interrupted by the translocation.