Carrier Screening for Genetic Conditions

Carrier screening is a term used to describe genetic testing that is performed on an individual who does not have any overt phenotype for a genetic disorder but may have one variant allele within a gene(s) associated with a diagnosis. Information about carrier screening should be provided to every pregnant woman. Carrier screening and counseling ideally should be performed before pregnancy because this enables couples to learn about their reproductive risk and consider the most complete range of reproductive options. A patient may decline any or all screening. When an individual is found to be a carrier for a genetic condition, his or her relatives are at risk of carrying the same mutation. The patient should be encouraged to inform his or her relatives of the risk and the availability of carrier screening. If an individual is found to be a carrier for a specific condition, the patient’s reproductive partner should be offered testing in order to receive informed genetic counseling about potential reproductive outcomes. If both partners are found to be carriers of a genetic condition, genetic counseling should be offered. What follows is a detailed discussion of some of the more common genetic conditions for which carrier screening is recommended in at least some segments of the population. Recommendations and Conclusions The American College of Obstetricians and Gynecologists (the College) makes the following recommendations and conclusions: General Recommendations • Information about genetic carrier screening should be provided to every pregnant woman. After counseling, a patient may decline any or all screening. • Carrier screening and counseling ideally should be performed before pregnancy. • If an individual is found to be a carrier for a specific condition, the individual’s reproductive partner should be offered testing in order to receive informed genetic counseling about potential reproductive outcomes. Concurrent screening of the patient and her partner is suggested if there are time constraints for decisions about prenatal diagnostic evaluation. • If both partners are found to be carriers of a genetic condition, genetic counseling should be offered. Prenatal diagnosis and advanced reproductive technologies to decrease the risk of an affected offspring should be discussed. • When an individual is found to be a carrier for a genetic condition, the individual’s relatives are at risk of carrying the same mutation. The patient should be encouraged to inform his or her relatives of the risk and the availability of carrier screening. The obstetrician–gynecologist or other health care provider should not disclose this information without permission from the patient. • It is important to obtain the family history of the patient and, if possible, her partner as a screening tool for inherited risk. The family history should include the ethnic background of family members as well as any known consanguinity. Individuals with a COMMITTEE OPINION Number 691 • March 2017 (Replaces Committee Opinion Number 318, October 2005; Committee Opinion Number 432, May 2009; Committee Opinion Number 442, October 2009; Committee Opinion Number 469, October 2010; Committee Opinion Number 486, April 2011) Committee on Genetics This Committee Opinion was developed by the American College of Obstetricians and Gynecologists’ Committee on Genetics in collaboration with committee members Britton Rink, MD; Stephanie Romero, MD; Joseph R. Biggio Jr, MD; Devereux N. Saller Jr, MD; and Rose Giardine, MS. This document reflects emerging clinical and scientific advances as of the date issued and is subject to change. The information should not be construed as dictating an exclusive course of treatment or procedure to be followed.