Molecular Genetics of Hereditary Breast Cancer in Ireland

Project Description

Funding Health Research Board Programme (Grant £200000).
Principal Investigator Dr David Barton.
Researchers Dr Bronagh O’hIci, Dr Trudi McDevitt, Ms Nuala Cody and Dr Nicola Miller.
Duration March 1998 - October 2001.
Collaborators Professor Peter Daly, St James’s Hospital and TCD; Dr Des Carney, Mater Hospital and UCD; Mr Enda McDermott, St Vincent’s Hospital and UCD; Professor Niall O’Higgins, St Vincent’s Hospital and UCD.


Breast cancer is the most common cause of cancer-related deaths for women in Ireland.

5-10% of breast cancer has a clear hereditary component, and the genetic basis for much of hereditary breast and ovarian cancer has been clarified with the identification of the BRCA1 and BRCA2 genes. The clinical implementation of these new molecular genetic discoveries is currently at a research stage.

This project proposes to set up a combined clinic offering genetic counselling and molecular genetic testing to affected and unaffected patients with a family history of breast and associated cancers.

If the family fulfils the criteria for hereditary breast cancer, blood samples will be taken from affected members to look for mutations in the BRCA1 and/or BRCA2 genes.

Where a mutation is found, predictive molecular genetic testing will then be offered to at risk family members, after careful counselling.

If no mutations are found in a family fulfilling the criteria for hereditary breast cancer, then a surveillance programme will be offered to at risk family members, with the aim of early detection of breast or ovarian cancer.

At a research level, this well-documented cohort of families will act as a major resource for many biomedical researchers in the field of breast cancer biology. The counselling and predictive testing will allow targeting of breast cancer surveillance towards those at most risk of the condition, with the aim of early detection and prevention.


  1. The Exon 13 Duplication in the BRCA1 Gene is a Founder Mutation Present in Geographically Diverse Populations.
    The BRCA1 Exon 13 Duplication Screening Group.
    Am. J. Hum. Genet. 67:207-212, 2000.