Table 3.

Analysis of MDR1 haplotypes and risk of childhood ALL

C1236TG2677T/AC3435TCasesControlsOR (95% CI)*
Hap 1CGC38.840.30.92 (0.58-1.45)
Hap 2CGT8.08.80.83 (0.37-1.88)
Hap 3TGC6.15.51.07 (0.41-2.75)
Hap 4TTT38.337.31.09 (0.68-1.75)
Hap 5xAx3.53.80.91 (0.28-2.92)
Hap 6Other5.24.31.54 (0.50-4.72)
Gene copies588738
Global likelihood ratio test§P = 0.970
  • * Haplotype ORs and 95% CIs were calculated using conditional logistic regression modeling haplotype probabilities (matching factors: date of birth, sex, Hispanic status, and maternal race). Each haplotype is compared with all other haplotypes.

  • Group of haplotypes that contain the variant A allele at the G2677T/A locus (includes CAC, CAT, TAC, and TAT).

  • Group of rare haplotypes with frequencies <5% and not part of Hap 5 (includes CTC, CTT, TGT, and TTC).

  • § Global likelihood ratio test done over all haplotypes. Estimates of exact P values were computed using Monte Carlo methods with 10,000 permutations.