Point estimates for ALDH2 ORs showed a tendency for risk reduction with the 487Lys allele for colon (crude ORs compared with Glu/Glu: Glu/Lys 0.48 and Lys/Lys 0.23 for males; Glu/Lys 0.83 and Lys/Lys 0.36 for females), but not for rectal cancer (crude OR: Glu/Lys 1.07 and Lys/Lys 0.66 for males; Glu/Lys 1.71 and Lys/Lys 1.11 for females). This evidence concerns the gene ALDH2 and rectal cancer.