Genetic Carrier Testing

Abstract Genetic carrier testing includes tests for the heterozygous status of a recessively inherited disorder in individuals who, although apparently healthy themselves, have a high risk of transmitting the genetic disorder to their offspring. Carrier testing will allow couples of childbearing age to make informed reproductive decisions. Genetic carrier tests are used by people who have a family history of an inherited disorder or carriership, reproductive partners of carriers and partners of individuals who have the disorder. A prerequisite for knowledge about a possible risk for relatives and the availability of testing is the dissemination of information in the family. Carrier testing can also be offered as a screening test to persons who do not have an a priori increased risk of being a carrier based on their family history. With new genetic testing technologies, it is possible to screen for a growing number of disorders simultaneously. Key Concepts Reproductive planning is the most important factor motivating genetic carrier testing. Family disclosure of genetic information is a prerequisite to knowledge about the risk and availability of carrier testing. Because of factors impeding the sharing of information in families and factors interfering with the decision about testing, the uptake for carrier testing in high‐risk families is often lower than expected. To minimize (time) constraints and maximize reproductive options, carrier testing before conception is advocated. Carrier screening is the detection of carrier status in persons who do not have an a priori increased risk of being a carrier based on their or their partners' personal or family history. Rapidly evolving genetic testing technologies facilitate carrier screening for a growing number of diseases simultaneously.