Is SMG9 deficiency the same as SMG9 disease or SMG9 syndrome?

Families and clinicians use several names for the same condition, including SMG9 deficiency, SMG9 syndrome, SMG9 deficiency syndrome, and heart and brain malformation syndrome. They generally refer to the rare disorder linked to the SMG9 gene.

Is there a treatment for SMG9 deficiency?

There is currently no approved treatment that corrects the underlying SMG9 gene problem. Care focuses on each person's symptoms. Zoja Research Foundation funds research toward better understanding and future therapies.

SMG9 Deficiency | SMG9 Syndrome & Research

What is SMG9 deficiency?

SMG9 deficiency is a rare, inherited genetic condition. It happens when both copies of the SMG9 gene do not work as they should. That gene helps cells handle certain messenger RNA through a process called nonsense-mediated mRNA decay.

Doctors may also call it SMG9 syndrome, SMG9 deficiency syndrome, or heart and brain malformation syndrome (sometimes abbreviated HBMS; OMIM 616920).

It is extremely rare. Published reports describe a small number of families worldwide. Because it is so uncommon, many families first hear the name after genetic testing.

This page is for information only. It is not medical advice. Care decisions should be made with a qualified clinician.

Signs and features

Not every person with SMG9 deficiency has the same features. Reports have included some combination of:

Developmental delay or intellectual disability
Congenital heart differences
Brain differences on imaging
Growth restriction or feeding difficulties
Distinctive facial features
In some people, vision, infection, or other medical issues

Severity varies. A genetic diagnosis of SMG9 deficiency does not tell you everything about one child's future.

Research and hope

There is currently no approved treatment that corrects the SMG9 gene itself. Supportive care addresses each person's symptoms.

Zoja Research Foundation funds work toward better models of the condition, comparison of research-grade gene therapy approaches, and the studies needed before any future clinical path. Our current research goal is to generate models, compare candidates, and select a lead construct.

Support for families Contact us

Common questions

Is SMG9 deficiency the same as SMG9 disease?

People use several search terms for the same condition: SMG9 deficiency, SMG9 syndrome, SMG9 disease, and SMG9 gene mutation. Heart and brain malformation syndrome is the name often used in medical databases.

How is it diagnosed?

Diagnosis is usually made with genetic testing, often after other evaluations. A genetics team can explain results for your family.

Is there a treatment?

There is no approved disease-modifying treatment yet. Research is early. The foundation exists to help move that research forward and to support families while it does.

How can I help?

You can share accurate information, connect with other families through us, or support the research campaign.

SMG9 Deficiency