BRCA – thus offering so-called direct to consumers services (directly to consumers). The application of these tests in the medical field has attracted criticism from many among human geneticists, as the results of the analyzes are sent online without the companies offering any genetic counseling service, limiting themselves to legal “disclaimers” that recall how the data provided should be discussed with your doctor.
The burden of the correct path to take to interpret the results is therefore entirely delegated to consumers, who, however, rarely have the necessary skills to understand the meaning of genetic risk factors.
The proliferation of companies offering genetic tests directly to private citizens has created another series of possible uses of these technologies, many of which are illegal but not easily prosecuted from a criminal point of view.
Consider, for example, a potential employer who carries out an unauthorized genetic analysis on the DNA of a candidate for employment, to verify that he has no particular predisposition to highly debilitating diseases, or an insurer who wants to verify the degree of genetic risk of a potential insured, or a spouse who suspects the partner’s infidelity.
However unlikely it may seem to non-experts, this type of analysis without the consent of the interested parties is technically possible already now, starting from minute quantities of biological samples, easily available for example from a cigarette butt or a used glass.
Obviously, most of these behaviors are prohibited by law. For example, in the United States, the Genetic Information Nondiscrimination Act (GINA) has already prohibited insurance companies from requiring genetic tests before underwriting a health insurance policy since 2010.
What can genetic testing really tell us in the medical field?
As anticipated, the first application of genetic tests in the medical field was that relating to Mendelian genetic diseases, ie diseases caused by alterations of single genes, whose inheritance follows the laws described by Mendel. This happened in the second half of the 1980s and since then the number of pathologies that can be analyzed has steadily increased, in parallel with the progress of the discovery of new variants associated with pathologies.
However, a radical change has occurred in recent years, approximately from 2010 onwards, with the development of technologies that have made possible the large-scale sequencing of large quantities of DNA at gradually lower costs (at the time of writing the sequence of an entire human genome can be obtained from around 600 euros).
With these premises, one might be led to believe that genetic testing is now capable of identifying all possible pathological variants, but such a conclusion would be wrong. This apparent paradox is explained by the fact that our current knowledge does not allow us to always and in any case establish whether a certain genetic variant is pathological or not.
Certainly this is possible in many cases – an example above all is the replacement of a single base (from T to A) in the gene of the beta chain of hemoglobin which leads to the replacement of an amino acid and causes sickle cell anemia. However, there are still many circumstances in which we are unable to predict the effects of specific genetic variants.