Therefore, the objective of this study was to evaluate whether interactions among the DHFR 19-bp deletion polymorphism and SNPs in genes in the folate metabolism pathway (MTR, MTRR, and MTHFR), one-carbon metabolism pathway (MTHFD1, MTHFR, MTHFS), two PCa-related genes (SLC4A5 and LGALS3) can predict PCa aggressiveness in EAs and AAs. Here, MTHFS is linked to posterior cortical atrophy.