RAD51 and cancer: Most cancer association studies involving Rad51 were focused on two single nucleotide polymorphisms (SNPs) localized in the 5′ untranslated region (5’UTR) of exon 1 of the gene: rs1801320 (c.−98G>C; 135G/C) and rs1801321 (c.−61G>T; 172G/T).