Supplementary Material for: Large scale population screening for BRCA1 and BRCA2 Ashkenazi founder mutations: perspectives of professionals providing oncogenetic consultations

Introduction: In March 2020, a nationwide population carrier screening for BRCA1/2 pathogenic variants among Ashkenazi Jewish women was initiated in Israel. We aimed to assess views regarding the program among professionals who provide oncogenetic counseling for detected carriers.
Methods: An online survey was distributed to clinical geneticists and genetic counselors.
Results: The participants’ impression was that most carriers did not comprehend the implications of a positive result when deciding to take the test. Some carriers, in retrospect, regretted taking it. Some had a known mutation carrier in the family, and some had a family history that justified a broader test (and so should not have been tested through the screening program). Eight survey participants (29%) reported they were initially against the screening program, but half of them are currently in favor of it. Most participants are unsatisfied with the way the screening is conducted and suggested various improvements. Emotional distress of carriers, as assessed by participants, was higher for those detected by the screening program, compared to those tested after oncogenetic counseling. No association was found between the age, profession and prior experience of participants and their responses.
Conclusions: While the general attitude towards the screening program is positive, most professionals feel the need to improve the current screening program by defining exclusion criteria, providing comprehensive pretest information and adding other BRCA1/2 founder mutations, as well as expanding the screening to include ethnicities other than Ashkenazi Jews.