Is Weaver Syndrome hereditary?

Weaver Syndrome is a genetic condition caused by pathogenic variants in the EZH2 gene, and while it is technically hereditary, the vast majority of cases occur as sporadic, de novo mutations. This means that in most instances, Weaver Syndrome is not inherited from a parent, but rather arises spontaneously in the affected individual.

Is Weaver Syndrome hereditary?

Weaver Syndrome is caused by genetic changes, specifically in the EZH2 gene located on chromosome 7. When the condition is inherited, it follows an autosomal dominant inheritance pattern, meaning only one copy of the altered gene is necessary to cause the syndrome. However, because most instances of Weaver Syndrome are de novo—meaning the mutation occurs for the first time in the affected child—it is rarely passed down through families.

What is the risk of recurrence for siblings or children?

For parents of a child with Weaver Syndrome, the recurrence risk for future siblings is generally low, provided neither parent carries the EZH2 mutation. If an affected individual decides to have children, there is a 50% chance of passing the pathogenic variant to each offspring. Genetic counseling is essential to assess individual risk factors and clarify the distinction between sporadic and familial cases.

How is Weaver Syndrome diagnosed and tested?

Diagnosis is confirmed through molecular genetic testing, which is recommended when clinical features such as rapid growth, macrocephaly, and characteristic facial features are identified. Current testing options include:

• Targeted gene sequencing: Analysis of the EZH2 gene.


• Multigene panels: Sequencing a group of genes associated with overgrowth syndromes to rule out similar conditions.


• Exome sequencing: A broader approach if initial EZH2 testing is negative but clinical suspicion remains high.

What is the role of genetic counseling?

Genetic counseling is a vital resource for families navigating Weaver Syndrome. Counselors help interpret complex test results, discuss the likelihood of recurrence, and explain reproductive options such as Preimplantation Genetic Testing (PGT) for those concerned about passing the gene to future generations. At DiseaseMaps.org, we have seen 6 members share their experiences, highlighting the importance of community support alongside clinical guidance.

Next steps

• Consult with a clinical geneticist to discuss EZH2 genetic testing.


• Request a referral to a genetic counselor to review family history and reproductive risks.


• Connect with the 6 members of the DiseaseMaps.org community living with Weaver Syndrome to share resources.


• Monitor for long-term health surveillance, as recommended by your specialist physician.

Medical disclaimer: This information is for educational purposes only and does not substitute professional medical advice, diagnosis, or treatment.

References

• NIH Genetic and Rare Diseases Information Center (GARD): Weaver Syndrome Overview.


• Orphanet: Weaver Syndrome (ORPHA:900).


• OMIM (Online Mendelian Inheritance in Man): #277590 Weaver Syndrome.


• DiseaseMaps.org: Community-reported data on Weaver Syndrome.