Osteonecrosis of the jaw is an uncommon but potentially serious complication of bisphosphonate therapy in multiple myeloma. Previous studies showed that the presence of one or two minor alleles of the cytochrome P450, subfamily 2C polypeptide 8 gene (CYP2C8) polymorphism rs1934951 was an independent prognostic marker associated with development of osteonecrosis of the jaw in multiple myeloma patients treated with bisphosphonates. The aim of this study was to validate the frequency of SNP rs193451 in 79 patients with multiple myeloma. In 9 (22%) patients developing osteonecrosis of the jaw, a heterozygous genotype was found, in contrast with those who did not develop osteonecrosis of the jaw (n=4, 11%) or healthy individuals (n=6, 13%). We found no differences in the cumulative risk of developing osteonecrosis of the jaw between patients homozygous and heterozygous for the major allele. We were unable to confirm a significant association between this polymorphism and the risk of developing osteonecrosis of the jaw.