Testicular germ cell tumor (TGCT) is a highly heritable cancer primarily affecting young white men. Genome-wide association studies (GWAS) have been particularly effective in identifying multiple common variants with strong contribution to TGCT risk. These loci identified through association studies have implicated multiple genes as associated with TGCT predisposition, many of which are unique among cancer types, and regulate processes such as pluripotency, sex specification and microtubule assembly. Together the identification of these biological plausible genes converges upon pathways involved in male germ cell development and maturation, and suggests that perturbation of them confers susceptibility to TGCT, as a developmental defect of germ cell differentiation.