Potocki-Lupski syndrome is caused by the duplication of part of chromosome 17 (17p11.2).
Children with Potocki-Lupski syndrome generally show late development and learning difficulties to varying degrees. Most have mild to moderate intellectual disabilities with a diagnosis of autism or autistic characteristics. Delayed motor development occurs due to reduced muscle tension. Sleeping problems with apnoea also occur, as does over-sensitivity to light and sound. Just over 50% of children with Potocki-Lupski syndrome have some kind of heart defect.
There are some typical facial characteristics associated with the diagnosis. Reduced muscle tension (hypotonus) is very common during infancy, and feeding difficulties are common. Acid reflux and vomiting often occur. Speech disorders and poor language development are seen in almost all children with this diagnosis. Some may have a high palate as well as crowded teeth.