Environment and Breast Cancer: Science Review

Evidence From Humans
Print this page
Cytochrome P450 CYP1B1 and catechol O-methyltransferase (COMT) genetic polymorphisms and breast cancer susceptibility in a Turkish population
Kocabas, N. A., Sardas, S., Cholerton, S., Daly, A. K., Karakaya, A. E. Archives of Toxicology. 2002. 76:11, 643-9.
Topic area
Body size - Genetic variability
Study design
Hospital based case-control study
Funding agency
Turkish Scientific and Technical Research Associat
Study Participants
Menopausal Status
The menopausal status of women included in this study is listed here.
Pre menopausal
Post menopausal
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
Incident, primary histologically confirmed cases from oncology hospitals. Controls were university staff, students, and individuals from the Turkish State Railways hospital reported to be in good health, not taking medications and not having any relatives with cancer diagnosis, matched on age, time of blood donation, and menopausal status
Exposures investigated
COMT and CYP1B1 allele frequencies, used PCR-RFLP
How exposure was measured
Biological Questionnaire, in-person
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Adequately controlled
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
Description of major analysis
Logistic regression analysis of COMT and CYP1B1 genotypes and breast cancer, including effect modification by BMI
Strength of associations reported
Overall, the CYP1B1*3 allele was associated with increased risk, adjusted OR=2.32 (CI: 1.26-4.25) whereas there was no significant association for COMT, adjusted OR=0.86 (CI: 0.46-1.6)
Analyses stratified by BMI showed that for those with BMI >24 and the CYP1B1*3 allele, the OR=2.78 (CI: 1.36-5.62) and BMI <=24 OR=1.52 (CI: 0.58-4.42)Analyses stratified by BMI showed that for those with BMI >24 and the COMT low activity allele, OR=0.87 (CI; 0.41-1.76) and BMI <=24 the OR=1.67 (CI: 0.53-5.25)