The yeast Saccharomyces cerevisiae RAD52 gene is involved in recombination and DNA double-strand break repair. Recently, mouse and human homologs of the yeast RAD52 gene have been identified. Here we present the genomic organization of the mouse RAD52 gene. It consists of 12 exons ranging in size from 67 to 374 bp spread over a region of approximately 18 kb. The first ATG is located in exon 2. Analysis of the promoter region revealed no classical promoter elements such as CCAAT or TATA boxes. Transcriptional mapping analysis revealed one major transcription start point. Analogous to the situation in yeast, transcription of the RAD52 gene in human skin fibroblasts and mouse Ltk- cells was not induced by methyl methanesulfonate treatment. Furthermore, no specific alteration in human RAD52 expression levels throughout the cell cycle was observed.