As the fields of pharmacogenomics and personalized therapy loom large, certain major ethical issues need to be addressed. These include the issues surrounding establishment of tissue banks, as well as discovery of incidental findings during genetic testing, and the problems of genetic discrimination and ethnically biased testing. In order to allow patients and the overall population to benefit from the advantages of personalized cancer therapy it is important that ethical guidelines are put in place.
Tissue, cells, and other data from patients who participate in research projects may have a significant impact on scientific knowledge and discovery. One prominent example of such an impact is the HeLa cell line, developed from cervical cancer patient Henrietta Lacks and currently used throughout the world in cancer research. However, questions concerning the ownership of patient samples are continually arising, as well as questions of how patients must be consulted and informed prior to using their samples in a particular investigation.
Currently, the Cooperative Human Tissue Network of the U.S.A. is involved in collecting tissue samples from patients, preserving them, and redistributing them for further research studies. In the case of tumor tissues, these are typically collected after surgery for tumor removal. For this tumor tissue banking and distribution, it is imperative to track and record a patient's informed consent. The Intergroup Specimen Banking Committee has recently implemented a checklist for informed consent which includes whether the patient approves of the sample being used for cancer research or for general medical research, and whether the patient should be contacted for any needed clinical follow-up (14). In general, the public appears open to the idea of donating their samples for reserach purposes. However, there has been some opposition to the more publicized projects due to issues with patient confidentiality and consent (15). Therefore, it is important for tumor tissue banks to consider all ethical implications when collecting and distributing samples.
DNA sequencing, previously noted as a technique commonly used to determine mutations that increase a patient’s risk of cancer, may present incidental findings with potential patient health or reproductive consequences that are unrelated to the original reason for the genetic test (1). These incidental findings are unlikely to appear in genotyping results, as genotyping checks only a handful of positions in genetic code with each corresponding to a particular known phenotype. Sequencing, on the other hand, checks the complete sequence and may uncover unexpected, clinically relevant results. Because of the potential for such findings, confidentiality of patient test results is very important. Clinical and scientific organizational bodies also suggest that patients should be able to decide if they want to be informed of any incidental findings (2). Professionals do have an obligation to disclose any findings that have significant health consequences for their patients, but only if they are actionable (2).
Both expected and incidental research findings can have serious implications for patients, perhaps even resulting in genetic discrimination, if new knowledge of disease risk or predisposition is uncovered. Genetic discrimination occurs when an individual is treated differently due to a perceived or actual difference in their genetic information that may increase their risk for or cause them to develop a disorder or disease (5). Patients may not be willing to undergo genetic profiling prior to personalized therapy because of fears of discrimination by employers and insurance companies on the basis of their results. In Canada, there is currently no legal policy specifically regarding genetic discrimination. However, the Canadian Human Rights Act protects Canadians from discrimination on the basis of disability, while the Personal Information and Electronic Documents Act protects citizens from allowing sensitive personal information to become public (12, 13). In the United States, Congress passed the Genetic Information Nondiscrimination Act in 2008, which specifically prohibits genetic discrimination by insurance companies and employers (6).
Ethnic Biases of Genetic Testing
Current ethical recommendations suggest that any potentially relevant genetic testing should be offered to all individuals, as race and ethnic groupings are inadequate to describe the range of variation found among individuals (8). However, certain polymorphisms are more prevalent in one population than another, suggesting that certain treatments may be more beneficial for certain populations or that certain populations may have a higher risk of a particular disorder. For example, the CYP2C19 polymorphism is found in 30% of Japanese cancer patients, while it is found in only 3% of Caucasian cancer patients (7).