Synonyms: SADDAN
Severe achondroplasia-developmental delay-acanthosis nigricans syndrome is characterised by the association of severe achondroplasia with developmental delay and acanthosis nigricans. It has been described in four unrelated individuals. Structural central nervous system anomalies seizures and hearing loss were also reported together with bowing of the clavicle femur tibia and fibula in some cases. The syndrome is caused by a Lys650Met substitution in the kinase domain of fibroblast growth factor receptor 3 (encoded by the FGFR3 gene; 4p16.3).
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
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Severe achondroplasia-developmental delay-acanthosis nigricans syndrome?
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Advocacy Organizations
The Chandler Project
The Chandler Project brings awareness and shines a light on transformative research surrounding achondroplasia and other skeletal dysplasias by offering support to a global community and network of patients, parents, and caregivers seeking information on scientific discoveries, pharmaceutical advancements and surgical treatment options.
Wave of Support, Inc
Empowering those affected by bleeding disorders and other rare disease through advocacy, resources, education, and support
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Clinical Trials
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