Synonyms: PLAAND
A rare genetic neurological disorder characterized by infantile onset of progressive leukoencephalopathy microcephaly severe global developmental delay and spasticity resulting in quadriparesis and posture deformation. Additional features include an abnormally exaggerated startle reflex seizures dystonia and hypomimia or amimia as well as progressive chest deformities and contractures of large and hyperextensibility of small joints among others. Thin corpus callosum is a prominent feature in brain imaging in addition to white matter abnormalities consistent with leukoencephalopathy.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version May 2026
Newly diagnosed with
PLAA-associated neurodevelopmental disorder?
Our RARE Concierge Services Guides are available to assist you by providing information, resources and connections as you navigate your rare disease journey.
Advocacy Organizations
PPP2CA Pathways
PPP2CA Pathways connects families, shares strength, and supports the research community in the search for answers to Houge-Janssens Syndrome type 3.
Don't see your organization here. Let us know here.
Clinical Trials
For a list of clinical trials in this disease area, please click here.