STUDY OF THE FREQUENCIES OF CYP1A1 GENE POLYMORPHISMS AND GLUTATHIONE-S-TRANSFERASE MU1 GENE IN PRIMARY BREAST CANCERS - AN UPDATE WITH AN ADDITIONAL 114 CASES

We studied the polymorphisms mi (Msp1 restriction site) and m2 (codon Val substitution) of CYP1A1 gene and the copy number of glutathione S- transferase mu1 (GSTM1) gene on 487 DNA of breast cancer primary tumou rs from Caucasian group. Tumours of patients aged 55 years and under a t diagnosis presented a great proportion of wild mi (- / -) genotype; 83.6% vs. 69.5% (p < 0.0006), and a higher percentage of copy number o f GSTM1 equal or under one copy; 65.2% vs. 53.4% (p < 0.011) for older patients, mi and m2 variants are closely linked(p < 0.0000). Tumour w ith a low copy number of GSTM1 is correlated with high histological gr ading (p < 0.01) and high Cathepsin D concentrations (p < 0.02). The c ombinations of different genotypes showed that association wild mi (-/ -) genotype and copy number of GSTM1 inferior or equal to one copy is correlated with an early onset of breast cancer primary tumour 44% vs. 6.4% for mi (- / +) or (+/+)genotype and copy number of GSTM1 superio r to one(p < 0.0000). The CYP1A1 gene wild form seems to be associated with early cancer development in Caucasian patients. (C) 1998 Elsevie r Science B.V. All rights reserved.