The WDR45B gene encodes a member of the WD40 repeat-containing proteins superfamily. Proteins of this family consist of a core unit of approximately 40 amino acids ending with Tryptophan (W) and Aspartic Acid (D), hence giving rise to their name. This core unit folds into a 7-bladed beta propeller structure that is responsible for regulating the assembly of multi-protein complexes. By carrying out this function, WD-40 proteins play a key role in several biological processes such as cell cycle control, apoptosis, signal transduction, chromatin assembly, vesicular trafficking and autophagy.
While the specific function of the WDR45B protein is yet to be fully understood, recent studies have suggested a link between WDR45B mutations and a neurodevelopmental disorder characterized by cerebral hypoplasia, mental retardation, spastic quadriplegia and epilepsy. This is further supported by the fact that other WD40 genes have been implicated in similar diseases; namely, WDR62-related primary microcephaly and WDR4-related microcephalic primordial dwarfism. 

The gene is located on the long arm of chromosome 17 and spans a length of 33.9 kb of DNA. Its coding sequence is contained within 11 exons and it encodes a 38.1 kDa protein product consisting of 344 amino acids. The gene is ubiquitously expressed in the human body but high expression is seen in the heart, skeletal muscle and pancreas. The truncating mutation p.R225* has been associated with intellectual disability in two different studies.