Individuals' experiences in genetic counseling and predictive testing for familial amyotrophic lateral sclerosis.

As clinical genetic testing in the amyotrophic lateral sclerosis (ALS) diagnostic setting increases, the identification of at-risk family members has also expanded. No practice guidelines specifically for predictive genetic testing exist, and few studies about the psychological impacts of testing in this subgroup have occurred, limiting the ability to tailor recommendations and counseling in this community. We surveyed asymptomatic individuals at risk for inheriting an ALS-associated gene mutation. The 80-question survey was designed using a combination of validated measures (General Anxiety Disorder; FACToR; Decision Regret Scale) and original items. Ninety participants completed the survey, including those who completed predictive genetic testing (N = 42) and those who did not (N = 48). Gene positive individuals experienced greater negativity, uncertainty, and overall psychological impairment (p = 0.002; p < 0.001; p = 0.001). Individuals who had not undergone testing reported thinking about their risk multiple times per day and experiencing more decisional regret than those who tested (p = 0.006). In terms of decision-making, being prepared for potential clinical drug trials was a more important potential benefit among those who underwent testing (p = 0.026). Participants valuing preparedness for clinical drug trials supports the concept that genetic testing for ALS will increase as research in gene-targeted therapeutics progresses. This study describes factors relevant to the genetic testing decision-making process and adaptation to results from the perspective of at-risk individuals, which can ultimately guide genetic counseling practice in this population.