p73 is a p53-related protein and a member of the family of transcription factors which include p53, p63 and p73. Although structurally and functionally related, it appears that the members of this family possess their own unique functions. No human genetic disorders have been linked to germ line mutations of p73; however, loss of heterozygosity has been associated with some cancers although the incidence is rare. Generally speaking, p73 appears to play an important role in gene transactivation and growth suppression. P73 participates in the apoptotic response to DNA damage and may function in connection with p53.