Trio exome sequencing identifies ultra-rare case of Skraban Deardorff syndrome

Abstract

Presentation
Individual (female) presented at 2 years of age due to concerns of developmental delay.

Diagnosis
Following multi-disciplinary assessment, she was diagnosed with autism spectrum disorder (ASD) and global developmental delay (GDD). Initial investigations for metabolic and genetic testing (microarray, Fragile X testing, and singleton exome sequencing) were normal, and MRI brain identified mild thinning of corpus callosum. However, trio exome sequencing identified a pathogenic de novo heterozygous variant in WDR26 gene (C.523-10A>G), confirming Skraban-Deardorff syndrome (SKDEAS).

Treatment
As for many children with global developmental delay, despite advancements in targeted precision therapies, management is supportive (including multi-disciplinary team input).

Discussion
In this article, we add to the spectrum of cases described by this ultra-rare syndrome while highlighting the rationale and utility of repeat genetic testing for patients with global developmental delay.