Abstract

This case report is directed at genomic testing and genetic counselling in unexplained rare genetic disorders of sudden unexplained death in childhood (SUDC) in a consanguineous couple where all three children, two boys and a girl, died between the ages of 1-4 years. No genetic test had been done previously. Whole exome sequencing (WES) of the parents later, showed that both carried a variant in the Desmoplakin (DSP) gene which has an autosomal recessive pattern of inheritance resulting in cardiomyopathy, and in the Sodium voltagegated channel, beta subunit 3 (SCN3B) gene which has an autosomal dominant inheritance pattern with variable penetrance, late or early onset and is associated with Brugada syndrome. From the case histories, it was possible to determine that the daughter was homozygous for the DSP variant, while the sons inherited the SCN3B variant. During post-test genetic counselling, the reproductive option given was preimplantation genetic testing for monogenic disorders and aneuploidies (PGT-M + PGT-A). This study reasserts the application of genomic testing such as WES in routine medical assisted reproductive practices.

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