Callosome

Gene: ADD1

Green List (high evidence)

4 unrelated individuals affected by ID and/or complete or partial agenesis of corpus callosum, and enlarged lateral ventricles. WES found loss-of-function variants - 1 recessive missense variant and 3 de novo variants. The recessive variant is associated with ACC and enlarged lateral ventricles, and the de novo variants were associated with complete or partial agenesis of corpus callosum, mild ID and attention deficit. Human variants impair ADD1 protein expression and/or dimerization with ADD2. Add1 knockout mice recapitulate corpus callosum dysgenesis and ventriculomegaly phenotypes. Three adducin genes (ADD1, ADD2, and ADD3) encode cytoskeleton proteins that are critical for osmotic rigidity and cell shape. ADD1, ADD2, and ADD3 form heterodimers (ADD1/ADD2, ADD1/ADD3), which further form heterotetramers. Adducins interconnect spectrin and actin filaments to form polygonal scaffolds beneath the cell membranes and form ring-like structures in neuronal axons. Adducins regulate mouse neural development, but their function in the human brain is unknown
Sources: Literature

Created: 16 May 2022, midnight

Mode of inheritance
BOTH monoallelic and biallelic (but BIALLELIC mutations cause a more SEVERE disease form), autosomal or pseudoautosomal

Phenotypes
Intellectual disability, corpus callosum dysgenesis, and ventriculomegaly; no OMIM #

Publications

• PMID: 34906466