MDM2 and osteosarcoma: In a different study of the p53 pathway, Toffoli et al. genotyped the Pro72Arg (rs1042522, Ex4+119C>G) SNP in TP53 and the MDM2 -309 promoter SNP (rs2279744, T>G) in 201 osteosarcoma cases and 250 controls from Italy [98].