Issues in the genetic assessment of predispositions for familial breast and ovarian cancer.

A rapid development in technology has enabled predictive testing for cancer suceptibility genes, such as BRCA1 and BRCA2. Already biotechnology companies and a number of university-based researchers are establishing service laboratories for the analysis of cancer predispositions. It is critical that high standards be established and maintained when conducting DNA testing, which should be performed in a research setting with proper Institutional Review Board approval. A cancer risk assessment programme should include the involvement of various experts in genetics, oncology, psychiatry and counselling. The legal, ethical and social issues involved in screening and testing for cancer predisposition genes are complex. Genetic counselling of subjects undergoing testing is needed to inform them of the potential risks as well as the potential benefits associated with presymptomatic testing.