A new cobblestone malformation complex disorder: Walker-Warburg syndrome associated with tectocerebellar dysraphia due to homozygous DAG1 mutations

Abstract

Objective: To describe a new phenotype of cobblestone malformation complex caused by homozygous frameshift DAG1 mutations leading to a complete absence of both α- and β-dystroglycan. Methods: We analyzed prenatal and postnatal imaging data of six patients from a consanguineous Israeli-Arab kindred diagnosed with Walker-Warburg syndrome (WWS) harboring this mutation. Results: The imaging studies demonstrated: cobblestone cortex, hydrocephalus, z-shaped brainstem, and in addition occipital encephalocele, vermian agenesis, and an elongated and thick tectum (tectocerebellar dysraphia). The studies also demonstrated periventricular hemorrhages and brain calcifications. Conclusions: DAG1 mutations cause a novel cobblestone malformation complex disorder: WWS associated with tectocerebellar dysraphia.