The United Nations Educational, Scientific and Cultural Organization (UNESCO) defines genetic data as information about heritable characteristics of individuals obtained by analysis of nucleic acids or by other scientific analysis. The Council of Europe understands this to be all data on the hereditary characteristics of a person or on the inheritance patterns typical of these characteristics within a group of relatives. Specifically, these could comprise biological ancestry, disease dispositions, but also information on certain abilities or living conditions. The European Parliament and Council also address the uniqueness of genetic data and the information they contain regarding the physiology or the health of the natural person which result from the analysis of a biological sample from that same person. 

According to the Council of Europe, the particular sensitivity of genetic data thus arises from the fact that, among other things, this type of information remains valid for long periods of time, that it can be used for assumptions about future developments (predictive potential) and finally that this kind of information can have a considerable impact on the life of the person concerned. For these reasons, the legislator has taken into account the specific features of genetic data during the legislation process of the Genetic Diagnostics Act. In view of that, genetic data should be considered more sensitive and more in need of protection from misuse than other kinds of personal medical information. This position, called "genetic exceptionalism", is controversial. Critics argue that predictive health information generally raises ethical, legal, and medical issues, and that data obtained from genetic analysis does not differ from other private and personal data. In contrast, the genetic re-identifiability of a person through her genetic fingerprint can be seen as a reason that stresses the particular sensitivity of genetic data: Unlike the relative anonymity of other personal data, the genetic fingerprint is a unique feature of each individual that unambiguously identifies it.