Andermann syndrome, also known as agenesis of corpus callosum with neuronopathy (ACCPN), Charlevoix disease and KCC3 axonopathy among other names,[1] is a very rare neurodegenerative genetic disorder that damages the nerves used to control muscles and related to sensation and is often associated with agenesis of the corpus callosum.

[1][2][3][4][5] It was first described in 1972 by Frederick and Eva Andermann et al.[3][6][7] Symptoms and signs involve both the central and peripheral nervous systems starting in infancy:[2][4] The inheritance pattern is autosomal recessive[4] and involves nonsense[8] and missense[9] mutations of the SLC12A6 gene which codes for an axonal cell membrane protein of the same name, that functions as a co-transporter of potassium ions and chloride ions.

[15] Autopsy examination of eight cases has shown both developmental and degenerative neuropathologic features in this disease, consistent with clinical duality as both a neurodevelopmental and neurodegenerative disorder.

These spheroids can occur throughout the cerebral hemispheres, explaining the psychotic symptoms by disconnection of the brain from itself by axonal functional disruption.

[16] A typical diagnostic workup includes:[18] Currently, no cure is known, but some symptoms may be treated, such as neuroleptics for the psychiatric problems.