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  • CDKL5 Development Disorder (CDD) is caused by mutations in the cyclin-dependent kinase-like 5 (CDKL5) gene, which provides instructions for making proteins that are essential for normal brain and neuron development. Diagnosis is via genetic testing.
  • CDD causes early onset seizures (usually within the first three months of life), and can lead to severe intellectual and motor impairment, abnormal muscle tone, gastrointestinal and feeding difficulties, and sleep and respiratory problems.
  • Although a genetic disorder, the mutation that causes CDD occurs randomly.
  • CDD is so rare there are fewer than 40 known cases in Australia, and fewer than 1,000 known cases around the world – although there may be more cases where access to genetic testing is poor.
  • The circumstances of each case vary depending on the child’s specific mutation on the CDKL5 gene – to date there are more than 200 known mutations.
An illustration depicting two people going up a ladder; one has more steps, though they are close in distance. The other has fewer steps, but they are at such a great distance that they are unclimbable.
A picture of Helen Leonard and Jenny Downs standing together.

Associate Professor Helen Leonard and Associate Professor Jenny Downs