Synonyms: 22q13.3 deletion | Phelan-McDermid syndrome
Monosomy 22q13.3 syndrome (deletion 22q13.3 syndrome or Phelan-McDermid syndrome) is a chromosome microdeletion syndrome characterized by neonatal hypotonia global developmental delay normal to accelerated growth absent to severely delayed speech and minor dysmorphic features.
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 September 2026
Newly diagnosed with
Monosomy 22q13.3?
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Advocacy Organizations
Care 4 the Caregivers (DAMES Charities Inc)
Care 4 the Caregivers aims to reduce caregiver burnout and build the resiliency of caregivers of children with disabilities by providing them with easy to access tools that focus on mindfulness, education, and community.
Chromosome 22 Central
To spread awareness and offer support and information on all chromosome 22 disorders.
Collaborative Research Advocacy for Vascular Anomalies Network (CaRAVAN)
As the research-based umbrella organization for all vascular anomalies, we are on a mission to develop a unified network of patients and their families, advocates, researchers, and clinicians who influence research from initial concept and design to patient care delivery
CureSHANK
CureSHANK’s mission is to accelerate the development of treatments for Phelan-McDermid syndrome. We are committed to helping improve speed and efficiency in the field, so that PMS treatments get from lab to loved ones more quickly. We believe that together we can build a better future for families dealing with Phelan-McDermid syndrome and other SHANK-related neurodevelopmental disorders.
Megan Oboyle
We exist to make today better and the future brighter for everyone living with Phelan-McDermid syndrome — from the moment of diagnosis to the delivery of treatments and cures.
PPP2CA Pathways
PPP2CA Pathways connects families, shares strength, and supports the research community in the search for answers to Houge-Janssens Syndrome type 3.
Project FAVA
Project FAVA is a 501(c)(3) non-profit patient advocacy group that promotes awareness of fibro-adipose vascular anomalies, educates patients, their families, and the global community, and provides helpful resources to those with FAVA. Project FAVA also advances research to move the needle towards more effective and less invasive treatment options for FAVA patients.
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
ReNU2 Foundation
ReNU2 Foundation supports families affected by RNU2-2-related neurodevelopmental disease. We foster collaboration, raise awareness, and advance research—pursuing a world where every family has testing, informed care, community, and treatment.
Uganda Alliance of Patients Organization
Supporting patients to access quality, safe and patient-centered healthcare services.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.