Oncologists are asked with increasing frequency to counsel their patients with respect to the medical, psychological and social repercussions of genetic testing for cancer susceptibility that may have been prescribed by physicians or carried out through direct-to-consumer tests. This article critically reviews the main ethical and social implications of BRCA testing, focusing on genetic responsibility and genetic discrimination. Genetic responsibility toward oneself and others is a highly debated implication of genetic testing for cancer predisposition that requires broad considerations of the boundaries between individual and community rights and a reappraisal of the notion of autonomy as relational. Physicians' duty to warn 'at risk' relatives can be an ethical quandary, yet confidentiality is key to the patient-doctor relationship. Mutation carriers may be subject to different forms and degrees of genetic discrimination and many individuals at risk have forgone BRCA testing to avoid potential discrimination. The scientific and medical community, together with patients and the public, has actively engaged against genetic discrimination. The legislation in many countries now protects against genetic discrimination by insurance companies and employers. Legal and regulatory issues are not the final answer to discrimination and profound cultural changes are required to create understanding and acceptance of all differences.