Genetic Epidemiology of Mammographic Breast Density

摘要

Mammographic breast density, has been shown to be a major risk factor for breast. We hypothesize that there is at least one major gene involved in the genetic variation of breast density. We propose to identify the chromosomal location for this gene(s) by linkage analysis. To do so, we have selected 23 large families providing the greatest information for linkage from a total of 426 breast cancer families in the Minnesota Breast Cancer Family Study. Mammograms and risk factor data were previously collected on these women through interview and mailed questionnaires. As of October 30, 2000, 384 samples from these families have been collected for analysis. We have also concentrated efforts on improving the breast density estimate. We have updated the subjective estimate of breast density to a computer-assisted estimate. Additionally, in the past year, we have performed several small studies to evaluate the reliability of this computer-estimate of density. The final year of the study will involve a genome screen for loci linked to the breast density trait, using a screening set of microsatellite markers that span the genome. The discovery of breast density genes could help in the identification of susceptible individuals to target prevention strategies.