Is 22q13 deletion / Phelan-McDermid Syndrome contagious?

TL;DR: Phelan-McDermid Syndrome, also known as 22q13 deletion, is a genetic condition and is absolutely not contagious. It cannot be spread through physical contact, respiratory droplets, blood, or any other environmental exposure, as it is caused by a structural change in an individual's DNA.

Is 22q13 deletion / Phelan-McDermid Syndrome contagious?

No, 22q13 deletion / Phelan-McDermid Syndrome is not contagious under any circumstances. There is no infectious agent, such as a virus, bacteria, or fungus, involved in the development of this condition. Because it is strictly a genetic disorder, it is impossible to "catch" or transmit the syndrome to family members, caregivers, or peers through social interaction or physical proximity. Living with, hugging, or caring for someone with Phelan-McDermid Syndrome poses zero health risk to others.

What causes Phelan-McDermid Syndrome?

Phelan-McDermid Syndrome is caused by a genetic deletion or mutation on the long arm of chromosome 22 at position 13 (22q13). In the vast majority of cases, this involves the loss of the SHANK3 gene, which is critical for the development and function of synapses in the brain. The condition typically occurs as a "de novo" (new) event during the formation of reproductive cells or early embryonic development, meaning it is usually not inherited from the parents. Because the root cause is a permanent alteration in the genetic code present from conception, there are no environmental triggers that can cause or "activate" the syndrome in a healthy individual.

Why is there sometimes confusion regarding contagion?

Misconceptions regarding the nature of 22q13 deletion / Phelan-McDermid Syndrome often stem from a lack of public awareness about rare genetic disorders. Because individuals with this syndrome may experience developmental delays, low muscle tone (hypotonia), or unique behavioral patterns, those unfamiliar with the condition may mistakenly attribute these traits to an illness that could be "passed on." It is essential to combat this stigma by reinforcing that Phelan-McDermid Syndrome is a biological difference in DNA, not an infectious disease process.

Key facts about the nature of 22q13 deletion

• Genetic Basis: It is caused by a deletion or mutation of the SHANK3 gene on chromosome 22.


• Zero Risk of Transmission: There is no risk of contagion through touch, sharing food, or everyday contact.


• Non-Degenerative: Unlike many infectious diseases, this is a neurodevelopmental condition, not a progressive infection.


• Community Insight: Currently, 35 individuals with 22q13 deletion / Phelan-McDermid Syndrome have joined our DiseaseMaps community, sharing their experiences to foster understanding and reduce the isolation often caused by societal stigma.

Next steps

• Consult with a clinical geneticist to better understand the specific genetic findings associated with 22q13 deletion / Phelan-McDermid Syndrome.


• Join the DiseaseMaps.org community to connect with other families who have navigated the social challenges of this diagnosis.


• Share educational resources from the Phelan-McDermid Syndrome Foundation with school administrators or social circles to clarify that the condition is strictly genetic and non-communicable.

Medical disclaimer: This content is for educational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of a qualified physician with any questions regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Phelan-McDermid syndrome.


• Orphanet: 22q13.3 deletion syndrome.


• Online Mendelian Inheritance in Man (OMIM): #606232 - Phelan-McDermid Syndrome.


• Phelan-McDermid Syndrome Foundation (pmsf.org).