What is CDKL5 Deficiency Disorder (CDD)?

CDKL5 Deficiency Disorder is a rare developmental epileptic encephalopathy caused by mutations in the CDKL5 gene, and this can manifest in a broad range of clinical symptoms and severity.

Although rare, and mostly de novo, the occurrence is believed to be ~ 1: 40,000 - 60,000 live births, making it one of the most common forms of genetic epilepsy.

The CDKL5 gene provides instructions for making proteins that are essential for normal brain and neuronal development. The CDKL5 protein acts as a kinase, which is an enzyme that changes the activity of other proteins by adding oxygen and phosphate atoms (a phosphate group) at specific positions.

CDKL5 was first identified in 2004, it stands for cyclin-dependent kinase-like 5, and its location is on the X chromosome. It mostly affects girls as affected boys rarely survive the pregnancy.

CDKL5 is needed throughout life, making CDD more of a neuro maintenance than a neurodegenerative disease. Studies have shown that the symptoms of CDD are reversible if the missing CDKL5 protein is reintroduced.