Molecular genetics & genomic medicine
Mosaicism for Cohen-Gibson Syndrome in a Female Individual With Overgrowth and Neurodevelopmental Delay
By Song F, Michels M, Betz B and 4 others.
Abstract
Background
The Embryonic Ectoderm Development (EED) gene encodes a core component of the Polycomb Repressive Complex 2 (PRC2), which regulates chromatin structure and plays a key role in embryonic development and cell differentiation. Pathogenic variants in EED are associated with overgrowth-intellectual disability syndrome (Cohen-Gibson syndrome, OMIM #617561), though reported cases are rare and typically involve heterozygous germline variants. This study presents an individual with confirmed postzygotic mosaicism in EED, contributing to diagnostic complexity.
Methods
A 12-year-old girl with tall stature, dysmorphic features, developmental delay, and congenital anomalies underwent clinical and genetic evaluation. Exome sequencing and targeted deep sequencing were used to identify and validate the genetic variant across multiple tissues.