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Kleefstra Syndrome 

What is Kleefstra syndrome?

Kleefstra syndrome is a disorder that affects many parts of the body and is characterized by developmental delay and intellectual disabilities. Because of its similarities to other conditions, testing has only recently become available to distinguish it. Due to this, the incidence is unknown.

What are the symptoms of Kleefstra syndrome?

Developmental delays and intellectual disabilities are two of the main symptoms of this syndrome. Affected people also have little or no speech, weak muscle tone, a small head, a wide skull, eyebrows that grow together in the middle, widely spaced eyes, nostrils that open to the front, a shrunken appearance to the middle of the face, a protruding jaw, rolled out lips, and a large tongue. High birth weights and childhood obesity are also symptoms of this condition.

Other common symptoms of this syndrome include structural brain abnormalities, congenital heart defects, seizures, genitourinary abnormalities, and severe respiratory infections. 

What causes Kleefstra syndrome?

The EHMT1 gene is either completely lost or has severe mutations that cause the loss of function in those with this syndrome. This gene is responsible for the instructions for the enzyme euchromatic histone methyltransferase 1. People with Kleefstra syndrome typically have a deletion of about one million base pairs on chromosome 9, where the EHMT1 gene is. This deletion causes the characteristic syndromes of this condition. If there is no deletion, there is a mutation in the gene that drastically alters the function of the enzyme it produces. 

In inherited cases of this syndrome, the pattern is autosomal dominant. It is usually a random event during the formation of reproductive cells that results in the deletion or mutations that cause Kleefstra syndrome. 

How is Kleefstra syndrome diagnosed?

A physical exam is conducted to find the characteristic symptoms of Kleefstra syndrome, as well as an evaluation of family and medical history. Molecular genetic testing is necessary to confirm the diagnosis. 

What are the treatments for Kleefstra syndrome?

A team of specialists is necessary for treatment, which consists of management of symptoms. Special education and physical, speech, sensory integration, and occupational therapy are all recommended from an early age. Renal, cardiac, and urologic issues should all be treated by specialists with standard treatment.  

Where can I find out more about Kleefstra syndrome?

Kleefstra Syndrome Articles