Special Needs: Kabuki Syndrome Genetic Testing

How common is Kabuki Syndrome?

Recently, I began working with a new child.  The child clearly had some autistic tendencies and a 'different' look which suggested to me some sort of syndrome.  As I discussed the child with the mom, the story the mother told me began to sound familiar.  Suddenly it occurred to me, the child was beginning to sound like a child with 'Kabuki Syndrome.'

Each child with Kabuki syndrome presents differently but the major similarities I saw between this child and another child I know with Kabuki syndrome were as follows:

• Feeding difficulties.
• Low muscle tone.
• Arched eyebrows with the eyebrow on either end of the brow almost non-existant.
• The shape of the eye.
• Sleeping difficulties.
• Sensory issues-obvious autistic tendencies.

I was very surprised to be looking at a child who seemed to have Kabuki syndrome.  It was my understanding that Kabuki syndrome is very rare what are the chances of meeting two kids with Kabuki?  

I immediately called Laura the Kabuki mom who is my expert on Kabuki.  Laura is very active in the Kabuki community and even hosts a Kabuki picnic for families of kids with Kabuki syndrome in the midwest.

Laura told me that Kabuki syndrome has been considered to be very rare.  Now that physicians are beginning to learn about Kabuki and how to identify Kabuki syndrome more cases are surfacing.  Apparently as more physicians are learning about Kabuki syndrome 'pockets' of Kabuki syndrome kids seem to be appearing near these physicians.

Genetics of Kabuki

It is speculated that Kabuki is a heterogeneous syndrome, meaning that multiple genes could potentially be involved. 

Recent research carried out by scientists at the University of Seattle, on August 15, 2010 the National Human Genome Research Institute seems to have discovered a gene responsible for approximately 70% of individuals with Kabuki Syndrome. The researchers used the newly developed technique of exome sequencing to identify the MLL2 gene mutations. Click here official press release.

This new discovery should assist in genetic identification of Kabuki syndrome which will most likely result in many more cases being diagnosed.

Diagnosing Kabuki

Up until this point, diagnosis has been based on the recognition of four (out of five) main characteristics, with the distinct facial features being imperative.

• Facial features: long palpebral fissures with eversion of outer third, arched eyebrows with sparse outer half, prominent eyelashes, prominent and/or misshapen ears, and depressed nasal tip
• Skeletal abnormalities: may include brachydactyly (shortness of fingers), brachymesophalangy (abnormal shortness of bone) and clindactyly (turning aside) of the fifth finger, and vertebral anomalies including scoliosis
• Dermatoglyphic abnormalities: including persistent finger fetal pads
• Intellectual disability (mild to moderate)
• Postnatal short stature  

For more information on Kabuki syndrome go to www.kabukisyndrome.com.