No association of risk variants for diabetes and obesity with breast cancer: the Multiethnic Cohort and PAGE studies

Cancer Epidemiol Biomarkers Prev. 2011 May;20(5):1039-42. doi: 10.1158/1055-9965.EPI-11-0135. Epub 2011 Feb 25.


Background: Body mass index is an established risk factor for postmenopausal breast cancer. Epidemiologic studies have also reported a positive association between type 2 diabetes (T2D) and breast cancer risk.

Methods: To investigate a genetic basis linking these common phenotypes with breast cancer, we tested 31 common variants for T2D and obesity in a case-control study of 1,915 breast cancer cases and 2,884 controls nested within the Multiethnic Cohort (MEC) study.

Results: Following adjustment for multiple tests, we found no significant association between any variant and breast cancer risk. Summary scores comprising the numbers of risk alleles for T2D and/or obesity were also not found to be significantly associated with breast cancer risk.

Conclusions: Our findings provide no evidence for association between established T2D and/or obesity risk variants and breast cancer risk among women of various ethnicities.

Impact: These results suggest that the potential for a shared biology between T2D/obesity and breast cancer is not due to pleiotropic effects of these risk variants.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Body Mass Index
  • Breast Neoplasms / etiology*
  • Breast Neoplasms / pathology
  • Case-Control Studies
  • Cohort Studies
  • Diabetes Complications / genetics*
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / genetics*
  • Ethnic Groups / genetics*
  • Female
  • Humans
  • Middle Aged
  • Obesity / complications*
  • Obesity / genetics*
  • Postmenopause
  • Prognosis
  • Prospective Studies
  • Risk Factors
  • SEER Program