Prenatal Genetic Carrier Testing Using Triple Disease Screening

Abstract

Rapid progress in gene discovery has dramatically increased diagnostic capabilities for carrier screening and prenatal testing for genetic diseases. However, simultaneous prenatal carrier screening for prevalent genetic disease has not been evaluated, and patient acceptance and attitudes toward this testing strategy remain undefined. To evaluate an educational, counseling, and carrier testing program for 3 genetic disorders: Tay-Sachs disease (TSD), type 1 Gaucher disease (GD), and cystic fibrosis (CF) that differ in detectability, severity, and availability of therapy. Potential participants received education and genetic counseling, gave informed consent, chose screening tests, and completed pre-education and posteducation questionnaires that assessed knowledge, attitudes toward genetic testing, and disease testing preferences. Medical genetics referral center. Volunteer sample of 2824 Ashkenazi Jewish individuals enrolled as couples who were referred for TSD testing. Genetic counseling, education, and if chosen, genetic testing for any or all 3 disorders. Acceptance of screening for each of the 3 disorders. Secondary outcomes include attitudes toward genetic testing and reproductive considerations. Of the 2824 individuals tested for TSD, 97% and 95% also chose testing for CF and GD, respectively. The frequency of detected carriers was 1:21 for TSD, 1 :25 for CF, and 1:18 for GD. Twenty-one carriercoupleswere identified, counseled, and all postconception couples opted for prenatal diagnosis. Pre-education and posteducation questionnaires revealed that patients initially knew little about the diseases, but acquired disease information and increased knowledge of genetic concepts. Education and genetic counseling increased understanding and retention of genetic concepts and disease-related information, and minimized test-related anxiety. Although individuals sought screening for all 3 diseases, reproductive attitudes and decisions varied directly with disease severity and treatability. These findings emphasize the importance of genetic counseling for prenatal carrier testing and may improve understanding, acceptance, and informed decision making for prenatal carrier screening for multiple genetic diseases.