CDKL5 deficiency disorder (CDD) is a rare developmental disorder characterized by epileptic seizures which begin within days or months of birth, and by severe developmental delay affecting neurological functions such as motor control, speech, and cognitive ability. This disorder is caused by mutations in the CDKL5 gene which reduce or eliminate expression or function of the CDKL5 protein.
The CDKL5 gene encodes the Cyclin Dependent Kinase Like 5 enzyme, which plays an important role in normal brain function, that is still being defined. The CDKL5 gene is present on the X chromosome, with most described CDKL5 patients being females (>80%), whereas boys with CDKL5 deficiency tend to show more severe symptoms. The seizures associated with CDKL5 are largely resistant to control with current anti-epileptic drugs. Likewise, there is no current treatment for the severe developmental delay or associated symptoms such as motor dysfunction. While approximately 1,500 patients have been diagnosed with CDKL5 deficiency globally, the prevalence is likely higher due to mis- and un-diagnosed cases.
Mutations in the CDKL5 often span the entire gene with all known pathogenic variants leading to defective protein. iPSCs in this catalog represent cell lines from male and female CDKL5 patients with different mutations. The male patients who donated are somatic mosaics and the paired WT cell lines were isolated from fibroblast and have not been engineered. These are considered isogenic as CDKL5 is an X-linked disorder. CRISPR corrected isogenic controls for the female patient lines are in development.