The reprimo (RPRM) gene family is a group of single exon genes present exclusively within the vertebrate lineage. RPRM genes are expressed across many species and are associated with developmental patterning of the gastrointestinal tract, brain and blood vessels. In humans, who have only RPRM and RPRM-Like (RPRML), the RPRM gene appears to be involved in tumor suppression in tumors of the gastrointestinal tract as well as in multiple other organs. Expression of RPRM is mainly induced by p53 after DNA damage, though expression of this gene has also been associated with expression of p73, another member of the p53 gene family. Upregulation of RPRM results in cell cycle arrest at the G2/M checkpoint. Epigenetic silencing of RPRM, mainly by DNA methylation of its promoter region, occurs at early stages of human cancer.