Quality in genetic counselling for presymptomatic testing--clinical guidelines for practice across the range of genetic conditions.

Presymptomatic testing (PST) is the performance of a genetic test on an asymptomatic individual at risk of a condition to determine whether the person has inherited the disease-causing mutation. Although relevant guidelines exist for specific diseases, there is no overarching protocol that can be adapted to any disorder or clinical setting in which such testing is offered. The objective of this European project was to develop a set of coherent guidelines for PST (for adult-onset monogenic conditions) for use by health professionals working in a range of disciplines, countries or contexts. To ensure the guidelines were appropriate and practice based, we organised a workshop attended by an expert group of practitioners with relevant health professional backgrounds from 11 countries. Models of service for offering PST were presented, the group then discussed different aspects of testing and the standard of care required to ensure that patients were prepared to make decisions and deal with results and consequences. After the workshop, several rounds of consultation were used with a wider group of professionals to refine the guidelines. The guidelines include general principles governing the offer of testing (eg, autonomous choice of the patient), objectives of genetic counselling in this context (eg, facilitation of decision making), logistical considerations (eg, use of trained staff) and topics to be included during counselling discussion with the patient (eg, consequences of both positive and negative outcomes). We recommend the adoption of these guidelines to provide an equitable structure for those seeking PST in any country.