Uptake of BRCA1 genetic testing in adult sisters and daughters of known mutation carriers in Norway.

This study was undertaken to examine transmission of information to first-degree relatives of BRCA1 mutation carriers and uptake of genetic testing. The intention was to consider revision of current legislation related to privacy if information on life-saving health care was not disseminated to at-risk family members. The Norwegian Radium Hospital provides clinical genetics services for families at high risk for hereditary breast and ovarian cancer. Together with major hospitals nationwide we provide medical surveillance. Nearly all expenses are covered by the National Health insurance. Because of the high number of families with founder mutations in BRCA1, we are in a unique position to gather information about these groups. Within a consecutive series, we identified 75 BRCA1 mutation carriers and registered information transmission and uptake of genetic testing 6 months or more after the index mutation carriers had been informed about their mutation status. These 75 BRCA1 mutation carriers had 172 living first-degree relatives, aged 18 years or older (84 females, 88 males). Forty-four out of 54 (81.5%) of females over 30 had opted for genetic testing. The testing rate among all relatives was 43%. At any age, 63 % of the females underwent genetic testing compared with 24% of the males (p<0.05%). The overwhelming majority of adult females at risk opted for genetic testing. Males with daughters more frequently than males without daughters asked for testing. The findings give neither reason to reconsider legislation on privacy, nor for us to consider more aggressive methods of contacting relatives.