Abstract
This paper focuses on the question of, "When is the best time to identify an individual at risk for a treatable genetic condition?" In this review, we describe a framework for considering the optimal timing for pursuing genetic and genomic screening for treatable genetic conditions incorporating a lifespan approach. Utilizing the concept of a carousel that represents the four broad time periods when critical decisions might be made around genetic diagnoses during a person's lifetime, we describe genetic testing during the prenatal period, the newborn period, childhood, and adulthood. For each of these periods, we describe the objectives of genetic testing, the current status of screening or testing, the near-term vision for the future of genomic testing, the advantages and disadvantages of each approach, and the feasibility and ethical considerations of testing and treating. The notion of a "Genomics Passbook" is one where an early genomic screening evaluation could be performed on each individual through a public health program, with that data ultimately serving as a "living document" that could be queried and/or reanalyzed at prescribed times during the lifetime of that person, or in response to concerns about symptoms of a genetic disorder in that individual.