• Specific facial features:
    • Deep set eyes
    • A prominent nasal bridge (where glasses rest on the upper part of the nose) and wide nostrils
    • A wide mouth with a cupid bow upper lip, full lower lip and widely spaced teeth
    • These are not so obvious in babies but become more obvious during childhood.
  • Developmental delay that becomes noticeable before the baby’s first birthday. People with PTHS are usually shorter than their family members.
  • Moderate or severe learning difficulties. Many children with PTHS will only learn to say a few words, or may not learn to speak at all, but can understand a lot of what is said to them.Some can speak quite well.
  • Low muscle tone (hypotonia). Although most children with PTHS do learn to walk around  the age of 4 to 6 many walk with a wide, unsteady gait.
  • Episodes of unusual breathing. Just over half of people with PTHS have episodes where they breathe very quickly (hyperventilate) followed by episodes where they don’t breathe for a time (apnoea). Doctors think that these episodes might be caused by excitement or anxiety .They usually only happen when the child is awake.
  • Epilepsy or seizures. Just under half of people with PTHS have epileptic seizures . Anti-epileptic medication is often effective to control seizures.
  • Constipation
  • Reflux
  • Small, clubbed or fleshy fingers and toes. People with PTHS sometimes have small hands and feet. Occasionally they can have ‘clubbing’ where the tips of their fingers or toes are wide and rounded. People with PTHS can have particularly fleshy pads in the tips of their fingers or toes.These are known as fetal pads.
  • Short sightedness or a squint.
  • Undescended testes. Boys or men with PTHS can have undescended testes.  Some cases of retractile testes have been seen.

People with PTHS are usually very happy and affectionate, but can become frustrated when they find it difficult to communicate.

Not every person with PTHS will have every single symptom of PTHS. Some of these symptoms – in particular a happy disposition and unsteady gait – can be confused with another condition called Angelman Syndrome. In most cases a genetic test can confirm a diagnosis of PTHS.

For more detailed information about the symptoms of PTHS, click here.