Gene-exposure interaction in occupational and environmental epidemiology: Results from an ongoing study

Abstract

ABSTRACT

A tissue bank is established in our department on a total of 659 persons whereof 341 are included in the

Nordic data base on somatic chromosome damage in humans. Genotyping of susceptibility genes relevant

to the exposures of the cohort is an ongoing undertaking in our laboratory.

GST's and mEH have been

genotyped for 80 persons so far,

CYP's for 20 persons. When the mean number of chromatide breaks and of

cells with aberrations were related to genotypes no statistical difference could be observed between the

genotypes for either parameter. No difference in cytogenetic damage between exposed and referents or

between smokers and non-smokers were identified for the two separate occupational studies these 80

persons represent. The results of the various cytogenetic endpoints were trichotomized and compared to the

genotype distribution. Although not statistically significant, the observed trend with higher percentage of

persons with polymorphic

GSTp1 in particular, but also for GSTq1 and mEH (exon 4) in the group with

high frequency of chromosome aberrations will be interesting to follow. For further follow-up studies, a

nested case-control study within the cohort would give a more rapid and less expensive approach than

analysing each study separately as a traditional case-control study. As high frequency of chromosomal

damage is associated with cancer development, the hypothesis to be tested would be whether genetic polymorphisms

for the most appropriate susceptibility genes could be an explanatory factor for this association.