Bioethics issues in human studies

Genotype information

Disclosure of test results

State of discussion

Should the test results be disclosed in any case?

Generally, the key bioethics position is the participant's right to know, or not to know which is addressed in the well established Universal Declaration on the Human Genome and Human Rights [12]. Furthermore, there are several documents dealing with the situation of genetic testing in general [7, 13, 14, 15, 16, 22]. A more detailed description which fits specifically to the research situation is given in the three documents prepared by the International Bioethics Committee (IBC) of the UNESCO [7, 13, 14].

Hereafter, three situations for disclosure of test results are decisive:

1. Does a free and explicit informed consent exist? This consent can only be given to a medical unit which is bounded by medical secrecy [7]. The decision of the participant about to know or not to know (if an option) should be established in advance to the commencement of the study
2. Are the data associated with an identifiable person? Where human genetic data have been anonymized, the opportunity for donors to receive the results of testing has been lost (see [13, 14]). Human genetic and proteomic data collected for the purpose of scientific research should not normally be linked to an identifiable person [14].
3. What was the stipulation of the Ethics Committee that had to approve the research plan [11, 14]?

Generally, the decision about disclosure, if an option, should always be preceded by a case-by-case analysis of harms and benefits with the aim of minimizing harms and maximizing benefits [7]. A clear benefit would be given in a situation where treatment for or prevention of the disease caused by the genetic predisposition is available [7].

In the view of the International Bioethics Committee the right to know test results may also be limited or suspended in exceptional cases for important medical, social or legal reasons [13]. A specific paragraph considers the possibility that this right may be denied if genetic data are collected and processed for epidemiological or statistical purposes [7, 13]. Generally, these possible limitations are poorly defined in other documents, not to mention in international or national legislation.

Another issue present in nutrigenomics research and not sufficiently considered by existing documents is the existence of different types of genotypes that are more or less related to the expected outcomes (i.e. diseases) implying different degrees of valuable information for the study participant. Furthermore, existing documents do not address that possibly, as time passes, tests results may become informative or of practical relevance. This could be throughout the course of a prospective study or even after the study has finished when possibly preventive or therapeutic means are developed.

How should the test results be disclosed to the participant? Should genetic counseling be requested in any case?

It is generally accepted that the results of genotyping should be disclosed by an appropriately trained and qualified person in an interactive manner, so that the patient is given a privilege to ask questions and obtain answers. Although it is uncertain what type and amount of information should be provided to the patient, there is a consensus that it must be adjusted to the level of comprehension, social and cultural background, and must provide psychological management [7, 13, 14, 16].

Where it is not feasible to inform the donors of biological material personally about their results, it might be appropriate to inform participants about overall results of research either individually or as a group via various measures of communication [13].

Nevertheless, in their 25 Recommendations on the ethical, legal and social implications of genetic testing, the working group invited by the European Commission pointed out that Europe-wide specific qualifications and quality standards in the field of genetic counseling are still needed [16].

In terms of applicability of existing rules to nutrigenomics research, it is obvious that the majority of key bioethics guidelines and position documents recommend or even require counseling services to be offered to the patient. However, this implies or refers to highly predictive diagnostic testing. Statements are scarce regarding the need for counseling in poly-etiological disorders and other complex genetic settings as present in nutrigenomics research. The genetic counseling used of patients with monogenic disorders and their families may not be applicable to nutrigenomics, which deals with more complex genetic patterns and typically does not allow for straightforward risk predictions in patient's relatives. Nutrigenomics data on gene variants are more likely to describe patient's individual status, including some preventable risks, in quite a similar fashion to some biochemical parameters (e.g. cholesterol levels).