Technical factors to consider when developing an Expanded Carrier Screening platform

Purpose of review Expanded Carrier Screening (ECS) is a genetic test able to detect carriers for a large number of autosomal recessive and X-linked diseases. Its clinical utilization is increasing but some technical aspects for its implementation are still controversial. Recent findings In the current literature, several aspects of ECS panel implementation have been addressed. One of the most relevant topics involves which genes/pathologies should be included in an optimized ECS panel and which variants should be reported. Here, we review the best practice criteria to refine and improve clinical utility and validity of an ECS panel. The criteria for optimal ECS panel implementation include the severity of pathologies, the prevalence of diseases in general population and a definitive or strong gene/disease association. Moreover, we discuss the main complications associated with the reporting of Variant of Uncertain Significance and the need for periodic reassessment.