This case report illustrates the power of a combination of trio exome sequencing, in silico splicing analysis, and mRNA analysis to provide sufficient evidence for pathogenicity of a relatively intronic variant in WDR45, and in so doing, find a genetic diagnosis for a 6-year-old patient with developmental delay and seizures, a diagnosis which may otherwise have only been found once the characteristic MRI patterns of the disease became more obvious in young adulthood.
Whole exome sequencing (WES) revealed a novel c.795delT mutation in the WDR45 gene affecting the girl, which was consistent with her eventual progression to a Rett-like syndrome phenotype including seizures along with a stereotypical cyclic breathing pattern.
By whole-exome sequencing, we identified an in-frame deletion in the WDR45 gene (c.161_163delTGG) in the hemizygous state in a 20-year-old man with a history of profound neurocognitive impairment and seizures.
Whole-exome sequencing revealed a de novo, heterozygous deleterious mutation c.400C>T (p.R13X) in WDR45, previously reported to be disease-causing and associated with early childhood global developmental delay and seizures other than epileptic spasms.