Meet Katie
Katie has a rare movement disorder called dystonia, which causes uncontrollable muscle spasms due to incorrect signals from the brain.
This forces the body into twisting, repetitive movements. Common dystonic patterns include toe-walking, foot clawing, hand or arm-twisting, torticollis – a deviation of the neck – and quietening of the voice.
Katie’s problems began at the age of two, but it wasn’t until she was referred to GOSH at the age of seven that she finally got a diagnosis. Since then, her condition has played a key role in advancing related scientific research.
A huge impact
Katie’s family met Professor Manju Kurian, Paediatric Neurologist and UCL clinician scientist at the hospital. “Once we got to Professor Kurian, we just knew Katie would be looked after – she knew her stuff,” says Katie’s mum Sarah. “We felt we weren’t at the end of the line when we came to her.”
For the past seven years, Professor Kurian has been working to understand what causes different types of dystonia. This condition has a huge impact on a child’s quality of life. It can be painful – children with the condition have difficulty walking and often have to use a wheelchair. If their hands are affected, it’s difficult for them to pick things up or to write, which makes it harder to study.
Genetic links
Professor Kurian’s team took DNA from their patients and, where possible, from their parents and siblings. They started by looking at a test called a Microarray, which analyses whether people have too much or too little genetic material.
Some children in the group had a loss of part of the genetic material on chromosome 19. What’s more, the deletion in chromosome 19 was in the same place for many of these children.
“When we found that overlapping region on chromosome 19, we thought that the faulty gene must be in there,” explains Professor Kurian. “And that’s how we found it. Within that region, there were only two genes that could have been the answer. Katie was crucial in providing a missing piece of the picture.”
Promising new treatment
Sarah remembers the difficult first years with Katie: “The type of dystonia that Katie was diagnosed with meant that she was declining. She used to be able to ride a bike, skip and hop but she lost the ability to do all these things over the years.”
Unfortunately, there’s no cure for most forms of dystonia, but thanks to new information about the genetic cause of dystonia, Professor Kurian was able to identify that for some patients there are ways of treating the symptoms through a procedure called deep brain stimulation. This is a treatment where small wires are placed in the part of the brain that controls movement, known as the basal ganglia. These stimulate the movement centre of the brain via a power pack implanted in the patient’s chest, like a pacemaker.
“No one knows exactly why stimulation of that site in the brain works,” says Professor Kurian. “But it does seem to help treat the symptoms of dystonia. Because we were able to identify the genetic cause of dystonia for patients like Katie, we found that just like another type of childhood dystonia, called DYT1 dystonia, the results from deep brain stimulation can be very dramatic for children with Katie’s newlyidentified type of genetic dystonia.”
Many children from all over the world have now been diagnosed with this new form of genetic dystonia as a result of Professor Manju Kurian’s original work and some have had deep brain stimulation - encouragingly, the majority have shown considerable benefit.
For some, the treatment has either restored or significantly improved independent walking and hand and arm movement. One patient was able to walk independently within two weeks, and in most patients, the improvement has been sustained over time.
Katie has now had her deep brain stimulation, and though it is early days, both she and the family report that she has benefited from this procedure- it is hoped that she will continue to show more improvement over time
Based in the Zayed Centre for Research, Professor Kurian’s team will grow brain cells to study this new genetic disease to try and understand why it happens. In the future they hope to use these cells to help develop even better treatments that will slow down or even reverse the progression of the disease, giving more children a brighter future.
Learn more about the Zayed Centre for Research into Rare Disease in Children.