BCL11B-related disease: a single phenotypic entity?

Craniosynostosis (CRS), the premature fusion of sutures between the skull bones, is characterised by a long "tail" of rare genetic diagnoses. This means that pathogenic variants in many genes are responsible for a minority of cases, and identifying these disease genes and delineating the associated phenotype is extremely important for patient diagnosis and for genetic counselling of families. One such gene is BCL11B. Heterozygous pathogenic variants in BCL11B have been described as causative for two Mendelian phenotypes, but until recently the gene remained only marginally associated with CRS. We have carried out a systematic review of literature, providing evidence that BCL11B-related disease (BRD) should be regarded as a single phenotypic entity. Furthermore, we describe four new patients, all of whom presented with CRS, thus expanding the phenotype of BRD and highlighting CRS as an important diagnostic clue.