The role of the clinical psychologist in the context of genetic counseling includes support for the process of decision-making for subjects at-risk, regardless of the decision that was made. For this, it is important to know the motivations behind these decisions. What may be considered advant-ageous and justifiable reasons to perform the PST for genetic diseases from the medical and public point of view, i.e., planning for the future, helping in the choice of a profession, family planning, improving quality of life and contributing to health, may not be recognized as such by the individual seeking the PST. This study addresses the motivation to perform the presymptomatic testing (PST) of subjects at-risk for three diseases, Familial Amyloid Polyneuro pathy (FAP), Huntington's disease (HD), and Machado-Joseph disease (MJD), compared with the motivation to perform the PST for Hemochromatosis (HH). FAP, HD and MJD are three genetic (monogenic) autosomal dominant late-onset diseases (LON-Ds) with no cure. FAP is a progressive sensorimotor and autonomic neuropathy of adult hood. HD is characterized by a triad of clinical symptoms of chorea (motor, cognitive and psychiatric symptoms), emotional distress and cognitive decline. MJD is characterized by slowly progressive clumsiness in the arms and legs, a staggering lurching gait, sometimes mistaken for drunkenness, difficulty with speech and swallowing, involuntary eye movements, and may be accompanied by double vision or bulging eyes, and lower limb spasticity. HH is a disease in which too much iron accumulates in parenchymal organs, leading to iron overload and subsequent organ toxicity and failure. The study participants consisted in 213 subjects at genetic risk for FAP, HD, and MJD and 31 subjects at genetic risk for HH, that were assessed through an interview to obtain sociodemographic data and the answer to one question about motivation to perform PST: "Which were the reasons that led you to perform the predictive test? "This study was carried out in Center for Predictive and Preventive Genetics (CGPP), Institute for Molecular and Cell Biology (IBMC), Porto (Portugal). This research used a mixed-method, since qualitative and quantitative techniques of data analysis were used. Before deciding to seek genetic counseling and to know their genetic status, subjects at-risk have naturally considered their motives and it was probably the pro-counseling reasons the ones dictating the motivation to perform the PST. This may suggest that in fact there is a prior self-selection to the test, i.e. only those considering to have emotional skills to go through the process, performing the test. Seven major categories were obtained. The most significant ones for FAP, HD and MJD were reasons related to the future, reasons related to others and reasons related to curiosity and to the need to know. For HH, the most important ones were reasons related to others and reasons related to the characteristics of the disease. The motivation of subjects at-risk to perform the PST for FAP, HD and MJD is external and unrelated to the disease, while the motivation of subjects at-risk to perform the PST for HH is related to the disease. Reasons related to others area common motivation: as subjects at-risk for FAP, HD and MJD, subjects at-risk for HH also chose reasons related to others as one of the most important motivations to carry out the PST. These subjects also care about the fact that they can transmit the disease to their children and care about other family members which are already ill. The category reasons related to others includes sub-categories that identify the person and the situation that led to the decision to perform a PST. Subjects at-risk are also concerned about the fact that they have to decide whether or not to have children and its economic implications.
El papel del psicólogo clínico en el contexto del consejo genético incluye brindar apoyo a los sujetos en riesgo en el proceso de toma de decisiones, independientemente de la decisión adoptada por el sujeto (conociendo o no el resultado de las pruebas genéticas). El estudio que se informa aborda la motivación para realizar las pruebas pre-sintomáticas (PPS) de sujetos en situación de riesgo para tres enfermedades: polineuropatía amiloide familiar (PAF), la enfermedad de Huntington (EH) y la enfermedad de Machado-Joseph (EMJ) y comparar con la motivación para realizar las PPS para hemocromatosis (HH). La muestra consistió en 213 sujetos portugueses que tenían riesgo genético para contraer las tres enfermedades y 31 sujetos en situación de riesgo genético para contraer hemocromatosis. Ellos fueron evaluados con una entrevista para obtener datos sociodemográficos y debían responder a una pregunta sobre la motivación para llevar a cabo las pruebas pre-sintomáticas. Se obtuvieron siete categorías principales y las siguientes son las más significativas para PAF, EH y EMJ: razones relacionadas con el futuro, razones relacionadas con los demás y razones relacionadas con la curiosidad y la necesidad de conocer. Para hemocromatosis, las más importantes resultaron ser razones relacionadas con los demás y las relacionadas con las características de la enfermedad. La motivación para realizar el test pre-sintomático (PST) de la PAF, EH y EMJ es externa y sin relación con la enfermedad, mientras que la motivación de los sujetos en situación de riesgo para la HH está relacionada con la enfermedad. Las razones relacionadas con los demás es una motivación común en ambos grupos. A los sujetos también les preocupa la posibilidad de transmitir la enfermedad a sus hijos.