The presence of the CDK13 genetic mutation does not rule out other possible genetic mutations or syndromes. This explains the wide spectrum of the extend a child can be affected. 

Up to 40% of CDK13 children are said to have a heart condition, but 60% do not. Some children have kidney or bladder issues. 

 

All CDK13 children have global developmental delay. They do progress however albeit at a slower pace than their peers. 

 

All CDK13 children have speech difficulties. Some children are non-verbal, some are very eloquent albeit with a lisp. 

 

All CDK13 children have a low muscle tone. This varies greatly between a slight reduction in muscle tone and a much more severe issue when a child remains in a wheel chair. The latter however is often found in children with additional genetic mutations. Milder difficulties improve remarkably with specialist physiotherapy exercises. 

 

All CDK13 children have reduced spacial awareness, gross and fine motor skills and proprioception issues, with a wide spectrum of the degree of being affected. These improve significantly with age and OT and Physio input. 

Most CDK13 children have swallowing and digestive difficulties which start at birth improve as they grow up. 

Some CDK13 children have flat feet and intoing, and require orthotic insoles and exercises to correct their leg-foot-ankle alignment. More pronounced cases require surgical intervention which produces good results.

Many CDK13 children exhibit sensory seeking behaviours, including mouthing objects (often mistaken for PICA). These are managed by removing any and all objects of potential mouthing of overeating, and close supervision. 

 

Many CDK13 children have a high pain threshold. This means an easier time at vaccinations and blood tests, but also represents a safety challenge as the child may be slow to react to burning or pain.