EFS for patients with ALL according to DHFR genotypes. (A) EFS curves for patients who are positive (+; black line) or negative (−; gray line) for DHFR AA−317 genotype. (B) EFS curves according to the genotypes of the polymorphism at the position −1610. The lower curve (black) represents EFS for homozygous CC patients (CC+); the line in the middle (dark gray) represents EFS for patients who have neither the CC genotype nor the T allele (CC−/T−). The upper curve (light gray) represents EFS for individuals that are carriers of the T allele (T+). (C) EFS for patients that are carriers (+; black line) or not (−; gray line) of DHFR haplotype *1. (D) EFS for patients that are carriers (+; gray line) or not (−; black line) of DHFR haplotype *4. The genotype and the number of patients in each curve, numbers of individuals with an event (in the parenthesis), as well as the P value, estimated by log-rank test for the survival differences between the patients groups, are indicated on each plot. Risk of event associated with the given genotype, expressed as a univariable HR with 95% CI, is indicated below the plots.