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Breast density and polymorphisms in genes coding for CYP1A2 and COMT: the Multiethnic Cohort
Yumie Takata1, Gertraud Maskarinec, Loïc Le Marchand
1Cancer Research Center of Hawaii, 1236 Lauhala Street, Honolulu, HI, USA. ytakata@fhcrc.org <ytakata@fhcrc.org>
BMC Cancer
|February 14, 2007
Summary
Genetic variations in CYP1A2 may influence mammographic density, particularly in non-dense breast tissue. Further research is needed to understand the impact of CYP1A2 and COMT gene polymorphisms on breast cancer risk.
Area of Science:
- Genetics
- Oncology
- Epidemiology
Background:
- Mammographic density is a key breast cancer risk factor, influenced by hormone replacement therapy (HRT).
- Genetic polymorphisms in estrogen metabolism enzymes are linked to breast cancer risk.
- This study investigates the relationship between mammographic density and specific genetic polymorphisms (CYP1A2*1F and COMT Val58 Met).
Purpose of the Study:
- To examine the association between mammographic density and CYP1A2*1F and COMT Val58 Met polymorphisms.
- To explore potential interactions between genetic factors and breast density in a multiethnic cohort.
Main Methods:
- Quantified mammographic density using a computer-assisted method.
- Genotyped participants for CYP1A2*1F and COMT Val58 Met polymorphisms via PCR/RFLP.
- Analyzed adjusted mean percent density by genotype using mixed models.
Main Results:
- A potential association was observed between the CYP1A2*1F C allele and increased percent mammographic density (p=0.11), specifically in controls, postmenopausal women not using HRT, and normal weight individuals.
- No significant association was found between the COMT Val58 Met polymorphism and breast density.
- The CYP1A2*1F association appeared to affect non-dense (fatty) breast tissue rather than dense areas.
Conclusions:
- The CYP1A2*1F genotype may influence fatty breast tissue composition, not dense areas.
- Differential susceptibility and hormonal status could explain discrepancies in findings across studies.
- Larger studies are recommended to investigate gene-gene and gene-environment interactions for CYP1A2 and COMT in breast cancer risk.
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