The changing landscape of carrier screening: expanding technology and options?.

Abstract

Carrier screening (CS) is a mechanism by which women and their partners can learn about their risks of having a child affected by a recessive genetic disorder.5 A carrier is a healthy individual who is not affected by genetic disease but nevertheless has one copy of a genetic mutation.6 Couples in which both individuals have a copy of the same genetic mutation are at increased risk of having a child who inherits the recessive genetic disorder.7 Theoretically, carrier identification and education regarding the inheritance of genetic mutations can serve as a form of “genotypic prevention” by enabling couples to prevent the generational transmission of specific genetic disorders.8 CS typically takes place in the context of reproductive healthcare,9 where results may be used to inform prospective parents of their options regarding family planning and prenatal diagnosis.10 CS is typically recommended on the basis of a family history of a genetic condition and for populations that have higher incidences of recessive conditions such as the Ashkenazi Jewish population.11 Some medical professional societies have recommended shifting away from targeting CS based on family history and ethnicity toward population-based CS for all women who are considering pregnancy or are already pregnant,12 specifically to screen for carrier status for cystic fibrosis (CF)9 and spinal muscular atrophy (SMA).14 In the last few years, CS panels15 have expanded to evaluate large numbers of mutations associated with a range of autosomal recessive and X-chromosome-linked inherited conditions including CF, SMA, Tay-Sachs Disease, sickle cell anemia and Fragile X syndrome.16 Several commercial laboratories have developed these expanded CS panels and market them to reproductive healthcare providers.17Despite the changing technological and commercial landscape of CS in the United States, little is known about the clinical and societal implications of expanding CS efforts to include and detect much larger numbers of genetic disorders. To this end, we report results of a study of professionals with expertise in genetics regarding their attitudes toward prenatal applications of expanded carrier screening (ECS). A primary aim of this paper is to describe genetics professionals’ perceptions of the benefits and challenges of expanding prenatal CS. A secondary aim is to situate these genetics professionals’ perspectives within the broader landscape of societal debates about appropriate integration of new risk assessment technologies into prenatal care. The results and following discussion demonstrate how new approaches to CS both resemble and diverge from previous prenatal surveillance technologies in ways that are likely to impact clinical practice and pregnant women’s reproductive choices and perceived responsibilities.