Genetic predisposition to breast cancer in selected individuals in Guernsey

Sotheran, Wendy (1998) Genetic predisposition to breast cancer in selected individuals in Guernsey. University of Southampton, Doctoral Thesis.

Abstract

It is estimated that 5-10% of all breast cancer may be hereditary. Mutations of BRCA1 and BRCA2 are predicted to cause approximately two thirds of familial breast cancer. Mutations of BRCA1 occur more frequently than mutations of BRCA2 (Szabo et al 1997). BRCA1 mutations are predicted to cause over 80% of familial breast and ovarian cancer, (Gayther et al, 1996).

The island of Guernsey has a population of 60,000 and has been subject to limited ancestry. The rate of breast cancer is similar to that of the United Kingdom. For women the risk of developing breast cancer is 1:12 at 80 years 1:100 at 50 years. For the period 1993-1996, 22-28 new cases per year were diagnosed in the Princess Elizabeth Hospital, Guernsey. Identification of families at risk, by genotype or phenotype, has clinical implications, in terms of screening and prophylactic surgery, for a significant number of women in this population.

Our study identified 29 families with breast cancer or breast and ovarian cancer, 63 women with early onset breast cancer, and 17 women with bilateral breast cancer. Index cases from these ascertainment groups were screened for germline mutations of BRCA1 and BRCA2. Of these probands three women carried BRCA1 mutations. No mutations of BRCA2 were identified.

Families with breast and ovarian cancer have a frequency of BRCA1 mutations consistent with other series. Families with site-specific breast cancer have a frequency of BRCA1 and BRCA2 mutations that is lower than expected. One novel mutation of BRCA1 is described.

This record has no associated files available for download.

Contributors

Download statistics