Weiss-Kruszka Syndrome | WKS Research

What is Weiss-Kruszka Syndrome?

Weiss-Kruszka Syndrome (WKS) is a very rare condition a person is born with. It is caused by a change in the genetic code of the ZNF462 gene. This gene contains the blueprint for a protein that acts as a regulator of brain and facial features during early child development.

WKS was first recognized in 2017 (PMID: 28513610), and so far, less than 50 cases have been reported worldwide. While it's rare - estimated to affect 1 in every 20,000 to 100,000 people - our medical knowledge about WKS, its full effects, and the best ways to manage it are constantly improving as more individuals are identified through genetic testing.

What are the most common signs?

Children with WKS may have:

Facial features such as ptosis (droopy eyelids) or a slightly different head shape
Developmental delays, especially in speech and motor skills
Low muscle tone (feeling “floppy” as a baby)
Feeding challenges during infancy
Differences in learning or behavior, autism or autistic-like features

Not every child has the same symptoms—some have many features, and others only a few.

What causes it?

WKS happens because there's a problem with the instructions from one of the two copies of the ZNF462 gene a person inherits. This genetic change stops the body from making enough of the essential ZNF462 protein, or causes the protein it does make to not work correctly. In most cases, this gene change is new (de novo), meaning it occurred spontaneously around the time of conception and was not inherited from either parent. Since the body needs a full amount of this protein to support healthy development, having only half the usual amount (because one gene copy is faulty) is simply not enough to prevent the syndrome (haploinsufficient).

How is it managed?

There is no single treatment, but a care plan focuses on supporting each child’s needs. This can include:

Early intervention (speech, physical, and occupational therapy)
Eye specialists for ptosis
Feeding support in infancy
Hearing checks, heart evaluations, or brain imaging if recommended

Most children benefit from a coordinated team of specialists who monitor development and health.

What can families expect?

The outlook varies widely. Some children have mild delays, while others may need more support throughout childhood. With therapies and early support, many children make steady progress.

Families often appreciate having a diagnosis because it:

Helps explain their child’s challenges
Guides doctors on what to monitor
Provides clearer expectations for development
Offers a way to connect with other families and researchers