Overview
Cancer epidemiology is a scientific discipline that aims to identify environmental, lifestyle and genetic factors that may be associated with an increased, or a decreased, susceptibility to the disease.
This discipline has made a substantial contribution to our current knowledge on the causes of breast cancer. Epidemiological studies have identified several reproductive (e.g. early age at menarche, late age at first birth, low parity, and late age at menopause) and lifestyle factors (e.g. increased alcohol consumption, overweight after menopause, and use of oral contraceptives and HRT) that are associated with a raised risk of developing breast cancer.
Research aims
The long-term aims of our genetic studies are
(i) to identify low-penetrance breast cancer susceptibility genes,
(ii) to determine their prevalence and contribution to overall cancer incidence in the population, and hence
(iii) to calculate personal risk estimates for genetic counselling by combining genotype and family history data.
We have several ongoing collections of blood samples and questionnaire data for genetic research on breast cancer including a national collection of 2-case families contacted through genetics clinics and other sources, a national collection of bilateral breast cancer cases and their relatives, unselected cases and unaffected women. We are pursuing several complementary approaches to gene finding through association studies of cases and controls: analysis of individual polymorphisms; high throughput analysis of SNPs in a large number of candidate genes; and analysis of SNPs in relation to intermediate phenotypes such as mammographic density, plasma levels of growth factors and urinary hormone measurements. Correlating genotype data with levels of such quantitative markers of susceptibility may be an efficient alternative to case-control analysis for gene discovery.
Our projects are an example of the close collaboration between research charities that are concerned about breast cancer. Most of our direct funding is from Cancer Research UK but all our laboratory work takes place in the Breakthrough Research Centre, specifically so that we can benefit from all the diverse scientific research that is carried out in the Breakthrough Research Centre. Our laboratory-based group also forms part of a larger genetics and epidemiology group lead by Professor Julian Peto and Dr Isabel dos Santos Silva at the London School of Hygiene and Tropical Medicine.
