ABSTRACT
To minimise potential misunderstandings, I should start by saying that the profession of genetic counselling has an important role in providing and mediating genetic information to the public, and that genetic counsellors usually perform this role successfully and sensitively. Medical geneticists who established the profession did it to reduce the suffering of both parents and children by helping the parents to have additional children. Moreover, genetic counselling has a unique potential for changing the traditional doctor-patient relationship. It is built on the ideal of personal autonomy and non-directiveness, which are the declared opposites of the traditional medical dictum of the ‘doctor knows best’. However, this promise has pre-requirements in order to be fulfilled. It demands mutual knowledge, trust and effective communication. There is always a risk of misunderstanding, misinterpretation or overestimating the information obtained. One of the most common errors is misunderstanding that genetic tests only reveal a probability and not a certainty and hence, misunderstanding that although a gene mutation may indicate that an individual is at a higher risk of developing a certain disease, it does not reveal the severity of the disease or the time of onset. Other areas of misunderstanding include misunderstanding the difference between genotype and phenotype, or between having a gene and having a disease; misunderstanding the difference between dominant and recessive alleles and hence, the meaning of carrier status; misunderstanding the difference between monogenic, polygenic and multifactorial diseases, meaning the difference between diseases caused by single genes, many genes or by a combination of genes and the environment; and misunderstanding the meaning of essential concepts such as penetrance and variable expressivity.
