Skraban-Deardorff syndrome

Skraban-Deardorff syndrome is a neurodevelopmental disorder characterized by intellectual disability, global developmental delay, and distinctive facial features. It results from pathogenic alterations in the WDR26 gene, which plays an important role in normal cellular function. The condition is inherited in an autosomal dominant pattern, meaning a single altered copy of the gene can lead to symptoms, and it typically presents in early childhood. This syndrome is very rare, affecting fewer than 1 in 1,000,000 people.

Individuals with Skraban-Deardorff syndrome consistently present with intellectual disability and global developmental delay, which are key features of the condition. Characteristic facial features include a thick lower lip vermilion, full cheeks, a hyperplastic maxilla, and coarse facial features, alongside widely spaced teeth. Other commonly observed findings, present in a majority of cases, include a happy demeanor and a thick upper lip vermilion, while a subset of individuals may experience features such as hypotonia, constipation, gastroesophageal reflux, feeding difficulties, and recurrent ear infections. Not all individuals experience all features, and severity varies considerably.

Skraban-Deardorff syndrome is caused by pathogenic variants in the WDR26 gene. This gene is important for normal protein function, and disruptions can affect multiple aspects of development, particularly neurodevelopment. The condition follows an autosomal dominant inheritance pattern, which means that having a single altered copy of the gene can result in the disorder. Although the core features such as intellectual disability and developmental delay are consistently observed, the severity and specific symptoms can vary even among affected individuals, underscoring variable expressivity. Genetic counseling is recommended to help families understand the implications for inheritance and family planning. Associated genes include WDR26.