A cDNA of PRDM5 was isolated based upon its homology to the PR domain of PRDM2. The gene encodes an open reading frame of 630 amino acids and contains a PR domain in the NH-terminal region followed by 16 zinc finger motifs. Through radiation hybrid analysis, PRDM5 was mapped to human chromosome 4q27, a region thought to contain tumor suppressor genes for ovarian, breast, lung, liver, colon, and other cancers. The gene has a CpG island promoter and is silenced in human breast, ovarian, and liver cancers. Upon infection of tumor cells, a recombinant adenovirus expressing PRDM5 causes G2/M arrest and apoptosis, suggesting that inhibition of PRDM5 may be involved in carcinogenesis.
