{{Rsnum
|rsid=117039649
|Gene=MDM2
|Chromosome=12
|position=68808776
|Orientation=plus
|GMAF=0.01194
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|geno1=(C;C)
|geno2=(C;G)
|geno3=(G;G)
|Gene_s=MDM2
}}[[rs117039649]], also known as SNP285 or SNP285C, is a SNP in an intron of the [[MDM2]] p53 binding protein homolog gene.
This SNP appears to only be found (so far) in Caucasians, and, in a subset of the alleles carrying the SNP309G>C ([[rs2279744]]) variant. 

A 2011 study comparing MDM2 promoter status among different cohorts of [[ovarian cancer]] (n = 1993) and [[breast cancer]] (n = 1973) patients concluded that [[rs117039649]](C) carriers were at reduced risk for both ovarian (odds ratio 0.74, CI: 0.58-0.94) and breast (odds ratio 0.79, CI: 0.62-1.00) cancer compared to SNP309G carriers (lacking SNP285).{{PMID|21316605}}