L-MYC polymorphism in cancer patients, healthy blood donors and elderly, tumor-free individuals in Russia

L-myc polymorphism was investigated in 95 breast cancer (BC), 63 colorectal cancer (CC) and 58 lung cancer (LC) patients, as well as in 122 healthy, m iddle-aged blood donors (HBDs) and 184 elderly, tumor-free individuals. The occurrence of the S allele in the BC cohort (57%) was significantly higher than that in middle-aged, healthy females (41%) and elderly, non-affected women (47%), implying involvement of the L-myc genotype in BC susceptibilit y (age-adjusted OR = 1.74, 95% Cl 1.11-2.73, p = 0.016). L-myc allele distr ibution in CC and LC was similar to that in controls. Contrary to earlier r eports, L:S allele frequencies ratio in elderly brood donors (EBDs) did not significantly differ from that in HBDs (0.49: 0.51 and 0.54:0.46, respecti vely). However, the S allele had a tendency to be over-represented among el derly compared with middle-aged smokers (55% vs. 44%; OR = 1.57, 95% Cl 0.9 8-2.50, p = 0.059), which implies that it may be linked with tolerance to s moking effects. (C) 2000 Wiley-Liss, Inc.