The most typical features of KBG syndrome include:
- Feeding difficulties in infants and children
- Developmental delay or learning difficulties
- Delays in reaching developmental milestones such as sitting up, crawling and walking. The appearance of first words or phrases or phrases is frequently delayed.
- Behavioural problems, such as anxiety, inability to stand still or concentrate and difficulties in social interaction, autistic features
- About half of the children with KBG syndrome grow slowly and unusually short for their age
Facial characteristics that appear to occur more commonly among the affected individuals include:
- A round or triangular shaped face
- Bushy eyebrows
- Large permanent upper middle teeth
- Slightly upturned or bulbous nose
- Low hairline
- Prominent ears
Other common problems may include:
- Hearing loss (mostly due to glue ear)
- Undescended testes in boys
- Seizures
- Vision problems (such as astigmatism, squinting)
- Scoliosis
- Small hands, curved 5th fingers (clinodactyly)
- Heart defects