Synonyms: CBL syndrome | Noonan syndrome-like disorder with JMML
A rare genetic polymalformative syndrome characterized by a Noonan-like phenotype associated with increased risk of developing juvenile myelomonocytic leukemia (JMML). The Noonan-like (NS) phenotype includes dysmorphic facial features (i.e. high forehead hypertelorism downslanting palpebral fissures ptosis low-set ears prominent philtrum and short neck with or without pterygium colli) developmental delay hypotonia and small head circumference. It can be associated with congenital heart defects or cardiomyopathy ectodermal anomalies and short stature. The NS phenotype is subtle or even inapparent in a large proportion of subjects but may occasionally be severe. Leukemia can be the only clinical manifestation of the syndrome.
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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Noonan syndrome-like disorder with juvenile myelomonocytic leukemia?
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Advocacy Organizations
Cache DNA
At Cache, we are on a mission to store the biomolecules of today in order to unlock the possibilities of tomorrow. Our vision is to create a scalable, sustainable, and standardized platform for reliable storage and access of biomolecules by combining chemistry, biology, automation, and computational tools to support patient advocacy groups worldwide and better connect samples to insights.
Heart of a Giant Foundation
The mission of the HGF is to achieve better health outcomes for heart diseases and related chronic health conditions in our communities and enhance the quality of life through health education, care support, and connection to community resources.
HeartCharged
Ending preventable deaths from undiagnosed heart conditions and sudden cardiac arrest, especially in young people, and providing patient-to-patient support.
Hypertrophic Cardiomyopathy Association
Providing support, advocacy, and education to patients, families, the medical community, and the public about hypertrophic cardiomyopathy and all thick heart muscle disorders, while supporting research and fostering the development of treatments.
Lymphangiomatosis & Gorham’s Disease Alliance
We connect patients and families to peers and networks of care, partner to advance new research, and educate the medical community to help all people navigating complex lymphatic anomalies have hope for a healthier tomorrow.
RASopathies Network
Our mission is to advance research to improve the quality of life for RASopathy families by bringing together clinicians, scientists, and families.
RareDNA Foundation
Dedicated to improving outcomes for individuals and families affected by rare DNA heart mutations by advancing awareness, access and action. We increase awareness among medical professionals and the public, provide education and resources on diagnosis and treatment, support scientific research, and advocate for faster diagnostic pathways, giving families the knowledge and care they need.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.