The following are the main features:
• Mild dysmorphic facial profile
• Low muscle tone in infancy
• Motor delay
• Mild to severe Intellectual delay
• Autism spectrum disorder
• Seizure has been reported but not common
• Other behavioural issues including anxiety disorder, attention-deficit/hyperactivity disorder, aggression, sleep disturbances
• Thin and brittle as well as slow growing hair and thin nails
• Abnormal dentition
• Undescended testicles
• Congenital heart defects
• Low thyroid function
• Bone anomaly
H1-4