Researchers at the Francis Crick Institute have discovered a promising treatment for CDKL5 Deficiency Disorder (CDD). CDD is a form of epilepsy that affects children.  Some symptoms included seizures, impaired cognitive development, and repetitive body movements. CDD is a devastating condition that can make a family’s life very difficult. Furthermore, it is a complicated disorder to manage. CDD was first identified in 2004 and as of now, the only treatment is medications to manage the symptoms. That is why this possible new method to treat the disorder is so interesting to me. A possible cure would change many lives. This video tells the story of a family with a child diagnosed with CDD.

CDD is an X-linked disorder. X-linked disorders refer to genetic conditions that are associated with mutations in genes on X chromosomes. This means that if a male is carrying this mutation, they will be affected because a man typically only has one X chromosome. A woman, on the other hand, typically has two X chromosomes so if she has a normal gene on the other X chromosome then she would likely be unaffected by the mutation, but has the risk of passing it on to her child. The ratio of boys affected by CDD to girls affected by CDD is roughly 8 to 1 according to PubMed Central.

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CDKL5 stands for cyclin-dependent kinase-like 5 which is a gene located on the X chromosome. CDKL5 is involved in the “formation, growth, and movement of nerve cells” (MedlinePlus). We know from AP Biology that a kinase is an enzyme that catalyzes the transfer of phosphates groups. This enzyme transfers a phosphate group to different proteins that alter specifically brain function. We know that kinases are involved in signaling pathways which makes them essential for coordinating cellular responses. Specifically in AP Bio, we looked at tyrosine kinase receptors. In this case, the kinase removes a phosphate from ATP to add it to tyrosine to created a fully activated phosphorylated dimer which will control cell growth and cell division. CDKL5 codes for an enzyme that plays a role in brain function and is responsible for the synthesis of proteins that help the brain develop.

Researches had the idea to boost another enzyme’s activity to make up for the lack of CDKL5. They looked at mice who lacked the CDKL5 enzyme. Scientists measured the level of a molecule that is targeted by the CDKL5 enzyme called EB2. In the mice that did not produce CDKL5, researches still found that EB2 was being phosphorylated so there had to be a different enzyme similar to CDKL5 that was phosphorylating EB2 by transferring phosphates. EB2 was still getting phosphorylated because CDKL2 (cyclin dependent kinase like 2) was identified instead. Researches now aim to increase the level of CDKL2 in people who lack CDKL5 to see if this can stop symptoms of CDD from occurring. Increasing levels of CDKL2 could “uncover better treatments that could truly make a difference in the lives of the children with this devastating condition” (Margaux Silvestre).

My hope is that this research will not only help children with CDD, but also inspire research on other kinases and help find alternative kinases to cure more diseases.