Clinical features
TBCK-related encephalopathy is a disorder where infants are often born with poor muscle tone (“floppy babies”) and may have trouble eating or even breathing.
Most commonly children have delayed developmental milestones (sitting, walking, speaking, etc).
Some children also develop seizures. Although some children with severe disease never learn to walk or talk, the symptoms can be quite variable, and a few children have been reported that achieve these milestones close to the usual time.
As patients get older, some develop distinct facial features and very large tongues.
More severely affected children may need mechanical ventilation for respiratory support or may require a tube for feeding.
Prevalence
The disease is very rare, but more common in children from Caribbean ancestry, particularly from Puerto Rico.
Inheritance
It is inherited when children get a mutation from each of their parents. There is a higher risk of the disorder if the two parents are related (i.e. first cousins.)