The cause for<unk>  was identified in 2011 as autosomal dominant mutations in the EZH2 gene on chromosome 7q36. EZH2 (Enhancer of Zeste, Drosophila, homolog 2) is the second histone methyltransferase associated with human overgrowth. It encodes the catalytic component of the PRC2 protein complex (Polycomb Repressive Complex 2), which regulates chromatin structure and gene expression, and has been found to repress transcription. EZH2 also has critical roles in stem cell maintenance and cell lineage determination, such as osteogenesis, myogenesis, lymphopoiesis and hematopoiesis. It can also be associated with mutations in the histone methyltransferase NSD1 gene on chromosome 5q35. The functions of NSD1 are not clearly known, but it is thought to act as a factor in influencing transcription, which contains domains involved in chromatin-mediated regulation during development. Most cases are found to be sporadic, with no family history of the syndrome, although there have been a few cases in families where autosomal dominant inheritance has been reported.
Weaver syndrome
Seaver Cassidy syndrome
Temple–Baraitser syndrome
Nance–Horan syndrome
Parinaud's syndrome
Adams–Nance syndrome
Frey's syndrome
Cohen syndrome