Patient Resources for
CDKL5 Deficiency Disorder (CDD)
CDKL5 Deficiency Disorder (CDD) is a serious and rare genetic disorder that is caused by a mutation of the cyclin-dependent kinase-like 5 (CDKL5) gene, located on the X chromosome.
The CDKL5 gene encodes proteins essential for normal brain function. Mutations in the gene are usually spontaneous ‘de novo’ occurrences, rather than inherited. Initially, CDKL5 mutations had been found in children diagnosed with cerebral palsy and autism, among other conditions, and the resulting disorder was classified as an early-onset seizure variant of Rett Syndrome. It is now known to be an independent clinical entity caused by mutations in a distinct X-linked gene and therefore a separate disorder with its own distinct characteristics.