September 2026 Research Update

EEG recordings in the first 2 years of life showed a pattern of increasing brain-wave disruption over time, and the more severe EEG changes tended to line up with more severe developmental scores. This study also mapped when certain seizure types were most common, highlighting a window in late infancy when particular seizure patterns appeared more often. Together, these results add detail to how seizures and EEG changes may evolve early in CDKL5 deficiency disorder and how some EEG features track with developmental severity. [1]

In this cohort of 48 infants and young children, EEG background features became more abnormal with age, including more discontinuity and generalized slowing. The researchers also reported that paroxysmal fast activity (brief bursts of fast brain activity) was more common in parieto-occipital regions, toward the back of the brain. These kinds of EEG details help describe what clinicians may see on EEG as children get older, although the study did not test whether changing EEG patterns changes outcomes. [1]

Seizure patterns clustered by age in this dataset, with epileptic spasms peaking around 7.5 to 11.5 months and tonic seizures around 6.5 to 14 months. The study also described sequential seizures often occurring as two events, commonly tonic seizures followed by spasms, around 7 to 11 months. The authors reported that several EEG features, including hypsarrhythmia and parieto-occipital epileptiform patterns, were linked with lower developmental scale scores in their analyses. [1]

For families, this adds a clearer picture of what EEGs and seizure types may look like during the first 2 years in CDKL5 deficiency disorder, and it suggests that certain EEG patterns tend to travel with more severe developmental challenges. This does not mean an EEG can predict an individual child's future with certainty, but it helps explain why EEG results are often discussed alongside development in research and clinical conversations. Because the evidence comes from a retrospective group followed in routine care, it mainly adds understanding now and could matter more later if confirmed and connected to treatment studies. [1]

Laboratory and mouse research this month focused on a specific chain of events that could help explain some brain changes in CDKL5 deficiency disorder: altered microtubules (the cell's internal tracks) leading to slower cargo transport inside neurons. The study connected this transport disruption to fewer connections between nerve cells and to behavior differences in mice. It also reported a partial rescue of transport by restoring a chemical tag on microtubules, offering a concrete biology target for future research. [2]

Researchers used both CDKL5 knockout mice and mice engineered to block CDKL5-related phosphorylation of a protein called MAP1S, and they found reduced dynein binding and movement along microtubules in neurons. In the MAP1S phosphomutant mice, they also reported impaired transport of AMPA receptors (proteins important for excitatory signaling), fewer dendritic spines, and fewer excitatory synapses. The same models showed increased microtubule stability and reduced tubulin tyrosination, which the authors linked to the transport problems. [2]

The study reported that the MAP1S phosphomutant mice showed anxiety-like behavior and differences in motor, social, and memory testing compared with typical mice. In neuron experiments, adding tubulin-tyrosine ligase (to restore tubulin tyrosination) was reported to restore dynein transport, suggesting the transport problem was not fixed and unchangeable in the lab setting. These findings are a step toward understanding mechanisms, but they do not show what will happen in people or which treatments might help. [2]

For patients and caregivers, this research mainly matters as early-stage work that tries to explain why brain cells may develop and function differently when CDKL5 is missing or not working. The practical value right now is that it identifies a specific pathway inside neurons (microtubule tagging and dynein-based transport) that could be tested in future studies, rather than pointing to immediate changes in care. What remains uncertain is how well these mouse and cell findings match the key symptoms in people with CDKL5 deficiency disorder, and whether targeting this pathway could be safe or effective in humans. [2]