Individuals with 22q11.2 deletion syndrome (22q11.2DS) can present with a wide range of features that are highly variable, even within families. The major clinical manifestations of 22q11.2DS include congenital heart disease, particularly conotruncal malformations (ventricular septal defect, tetralogy of Fallot, interrupted aortic arch, and truncus arteriosus), palatal abnormalities (velopharyngeal incompetence, submucosal cleft palate, bifid uvula, and cleft palate), immune deficiency, characteristic facial features, and learning difficulties. Hearing loss can be sensorineural and/or conductive. Laryngotracheoesophageal, gastrointestinal, ophthalmologic, central nervous system, skeletal, and genitourinary anomalies also occur. Psychiatric illness and autoimmune disorders are more common in individuals with 22q11.2DS.

Complex cortical dysplasia with other brain malformations-12 (CDCBM12) is an autosomal recessive disorder of developmental neuronal migration characterized by severe to profound neurodevelopmental delay with absent speech, central hypotonia, peripheral spasticity, cortical visual impairment, and dysmorphic craniofacial features. Affected individuals usually have feeding difficulties and show minimal developmental progress of motor or cognitive skills. Most have microcephaly and develop early-onset refractory seizures. Brain imaging shows cortical abnormalities, such as lissencephaly and pachygyria, as well as other brain malformations, including thin or absent corpus callosum, dysplastic basal ganglia, and mild cerebellar hypoplasia. Due to the function of CAMSAP1 in microtubule stability and maintenance, this disorder can be classified as a 'tubulinopathy' (Khalaf-Nazzal et al., 2022). For a discussion of genetic heterogeneity of CDCBM, see CDCBM1 (614039).