One small case-only study (n = 98) considered concentrations of annual chlorinated solvents modeled at the census tract level and reported an interaction between high trichloroethylene and OGG1 rs293795 genotype and childhood medulloblastoma/PNET (Lupo et al. 2012); the case-only study design did not allow the researchers to estimate marginal effects for the chlorinated solvents. This evidence concerns the gene OGG1 and medulloblastoma.