Effectiveness of expanded prenatal screening among consanguineous couples of Afghan descent.

Objective: The American College of Medical Genetics recommends extensive carrier screening among consanguineous couples, yet limited information is available regarding its performance among specific populations. We describe the potential utility of a large expanded carrier screening panel (>500 genes) for Afghan couples with consanguinity. Method: A retrospective chart review was conducted of all patients who reported consanguinity and had genetic counseling consultation between 2010 and 2021 at our institution. Results: Thirty-six women of Afghan descent reported consanguinity. Nineteen (53%) did not have known autosomal recessive disease risk (no prior fetus/child with suspected syndrome), 11 (31%) had apparent disease risk (fetus/child with symptoms suggesting syndrome but no specific diagnosis), and six (17%) had known molecular diagnosis for a prior child with a recessive syndrome. Of the six women with known molecular diagnosis for prior child with syndrome, five had known pathogenic variants confirming a genetic disorder, and one had highly suspicious variant of uncertain significance in the family. Among these six, five (83%) could have been identified with a 787-gene prenatal carrier screening panel. Conclusion: Large, expanded carrier screening panel appears to be an effective method for identifying disorders among consanguineous Afghan couples and should ideally be considered preconceptionally.