Table of definitions

Genetic Data

  • In a strict sense genetic data is information about the genetic code (DNA, RNA and protein sequences) on the human chromosomes present in the nucleus and mitochondria of the cells of an individual, and about the number and state of the chromosomes. Such data determine the individual's genetic identity and are conserved through generations. This is the procedure which most people have in mind when they speak of genetic testing.
  • In a broader sense, the term genetic data, when applied to an individual, may be taken to mean any information about the operation of heredity in the case of that person. This information may be derived in a number of ways.
    1. The taking of a family history.
      In this process information collected about the presence of genetic conditions in other members of a person's family enables conclusions to be reached about that person's genotype. These conclusions, of course, depend on our knowledge of patterns of inheritance and may be confined to statements of possibility. Nonetheless, the statement that a person has a fifty per cent chance of having a particular genetic condition because one of his parents had that condition amounts to genetic information. (Such statements, of course, were possible even before the existence of genes as such was known. At the time that Mendel developed his system, the existence of DNA was undiscovered. All that was known was that there were rules of heredity; the precise operation of the process was not to be discovered until the twentieth century.)
    2. Direct observation of a person's phenotype.
      On the basis of this observation it may be possible to reach a conclusion as to the presence in that person's genetic makeup of one or more particular genes. An example of this process would be the diagnosis, on the basis of observation of phenotypical features, of Down's Syndrome, a condition that is known to be based on a genetic factor. The fact that a person has Down's Syndrome means that very specific conclusions (the existence of trisomy 21) can be reached about his or her genotype.
    3. An analysis of proteins expressed in an individual.
      Such an analysis will indicate the presence of the genes that have coded for these proteins.
  • A decision is therefore required as to whether principles pertaining to genetic data should include all the above forms of genetic information, or whether they should be restricted to information about the genetic DNA, RNA and protein sequences. The arguments in favour of each position are:
    1. In favour of including all forms of genetic information. Consistency requires that any regime be applied equally to all forms of genetic information, however it is obtained. There is no reason in principle why information about the genetic DNA, RNA and protein sequences should be treated as more significant than other information which is effectively information about DNA, although obtained by a method other than DNA sequencing.
      Exclusion of family history information from the scope of any recommendations could mean that protection of a person from breach of confidentiality becomes dependent on the method by which the information was obtained. As a result an assessment of genetic risk derived from a family history could be used in a discriminatory way in the context of employment or insurance.
    2. Against including all forms of genetic information. DNA testing is capable of disclosing a much greater range of information about an individual than indirect methods. Emerging chip technology will enable tests to be done for many hundreds of sequences at a time, thus enabling information to be elicited relating to many conditions. DNA sequencing is therefore much more powerful and potentially informative than phenotypical observation or family history-taking.
      The public perception also is that the results of DNA tests are matters of greater sensitivity than the selective, focused information obtained from, say, family history-taking. A person's genotype is seen as revealing something about his or her essence. It therefore falls into a category of particularly intimate information, needing special protection.
  • For the purposes of this Report, we recommend that the broader rather than the narrower definition of genetic data be used. This is consistent with the position taken in the Report of the IBC on Confidentiality and Genetic Data.

Relevant documents

[ 50 ] Recommendation Rec(2006)4 of the Committee of Ministers to member states on research on biological materials of human origin