CDKL5 Disorder

What is CDKL5 disorder?

CDKL5 disorder is a rare neurodevelopmental condition that is characterized by early-onset epilepsy (seizures), low muscle tone and developmental challenges. Other common symptoms include difficulty with vision, sleep disturbances, trouble with feeding and/or swallowing, impaired growth, reflux, constipation and orthopedic complications from low muscle tone such as scoliosis (curvature of the spine). Read more about symptoms.

Although CDKL5 disorder was previously classified as the early-onset-seizure variant of Rett syndrome, it is now considered an independent condition. In fact, one study of CDKL5 disorder (Fehr et al, 2013) has shown that less than a quarter of those affected met clinical criteria for early-onset Rett syndrome.

What causes CDKL5 disorder?

The disorder is caused by variants in the cyclin-dependent kinase-like 5 (CDKL5) gene. CDKL5 codes for an enzyme that plays an important role in brain development and function. Disease-causing variants in the CDKL5 gene include missense variants (spelling errors in the DNA code causing one amino acid to be substituted for another) and truncations or deletions (a shortened version or missing piece of the gene that can lead to the protein not being made).

CDKL5 is on the X chromosome, one of the sex chromosomes. Females have two copies of the X chromosome and males have one X and one Y chromosome. The majority of children with CDKL5 disorder are girls who have a CDKL5 variant on one X chromosome. However, there are boys who have a CDKL5 variant on their only X chromosome who can show features of the disorder.

How we care for CDKL5

While there is currently no specific treatment for CDKL5 disorder, the multidisciplinary CDKL5 Clinic can create a care plan to match your child’s needs and help her reach her full potential, as well as resources and help in connecting with community and educational services.

Our physicians and therapists are experienced in treating children with CDKL5 and come from a variety of specialties, including:

  • Neurology (including epilepsy, neurogenetics, behavioral neurology and sleep)
  • Gastroenterology, nutrition and feeding
  • Genetics
  • Neuro-ophthalmology
  • Orthopedics

Our team, in turn, is learning from patients and their families and is conducting ongoing clinical and laboratory research studies with the goal of improving care for this rare condition. Read more about CDKL5 research at Boston Children’s.

For information and appointments

Please visit the CDKL5 Clinic website or call our clinic coordinator at (617) 355-8994.