Synonyms: Isochromosome 18p
Tetrasomy 18p is a very rare structural chromosomal anomaly affecting multiple body systems and characterized clinically by craniofacial abnormalities delayed development cognitive impairment changes in muscle tone distinctive facial features and rarely renal malformations.
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 April 2026
Newly diagnosed with
Tetrasomy 18p?
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
Rare Chromosome Disorder Support Group – Unique
Through sharing knowledge and lived experience, Unique helps families and professionals navigate the world of chromosome and gene disorders
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.