We therefore hypothesized that single nucleotide polymorphisms (SNPs) (located in regulatory regions involved in regulation of expression and alternative splicing as well as SNPs introducing changes to the protein sequence) in genes encoding PD-1 and PD-L1 molecules may be associated with the development and outcome of renal cell carcinoma (RCC). The gene discussed is PDCD1; the disease is renal cell adenocarcinoma.