While there are many symptoms associated with GPT2 Deficiency, these signs and symptoms can vary greatly from person to person. There is still a lot to learn about this disease, so it is important to understand that an individual may not exhibit all of the symptoms below and some may emerge at different points during childhood.

Typical Signs

Some of the earliest signs can be detected in infancy. These include:

  • Global developmental delay, including delayed gross, fine, speech and cognitive milestones.
  • Feeding problems resulting in low height and weight percentiles, and sometimes failure to thrive .
  • Hypotonia (low muscle tone).

GPT2 Deficiency affects males and females equally.


Symptoms can change throughout childhood and there is great variation in their presentation. There are also many interventions and treatment options that serve to address the following symptoms:

  • Mild, moderate, or severe intellectual disability.
  • Postnatal microcephaly (small head size or decreased brain growth).
  • Hypotonia (low muscle tone) during infancy, which changes to hypertonia (high muscle tone) later in childhood.
  • Oral-motor dysfunction, causing difficulty speaking and eating.
  • Spastic diplegia or paraplegia (weakness or loss of function of lower limbs)
  • Muscle and coordination disorders including dysarthria, ataxia and apraxia.
  • Hyperreflexia (overactive reflexes)
  • Seizures

We hope to help improve standards of care for individuals with GPT2 Deficiency. While there are no known treatments at this point, many therapies can help manage and improve symptoms. Early intervention is important for younger children, and other therapies can include physical therapy, occupational therapy, speech therapy and feeding therapy.

There is also ongoing research focused on finding a cure. Learn more about our research here.