Selectins are responsible for the early stages of cell migration as they control cell adhesion. They make the microenvironment permissive for metastatic events by promoting the activation of other cell adhesion molecules (CAMs). We employed several robust bioinformatics tools to evaluate gene sequence; single nucleotide polymorphisms (SNPs) in intronic and UTR regions; and missense SNPs with amino acid change in L-selectin (SELL), E-selectin (SELE), P-selectin (SELP) and PSGL-1 (SELPLG). We demonstrated that gene polymorphisms rs2229569, rs1131498, rs4987360, rs4987301 and rs2205849; polymorphisms rs3917777, rs2205894 and rs2205893 of SELP gene; rs7138370, rs7300972 and rs2228315 variants of SELPLG gene; and rs1534904 and rs5368 polymorphisms of SELE gene may produce important alterations in the DNA structure and consequent alterations in the morphology and function of the corresponding proteins. These Selectin polymorphic variants deserve further investigation in cancer patients, as they may become useful clinical markers for risk determination, diagnostic and prognostic biomarkers or even targets for targeted therapies.