EEC syndrome

EEC syndrome (Ectrodactyly-Ectodermal dysplasia-Cleft lip/palate syndrome) is a rare genetic disorder characterized by a triad of clinical features: ectrodactyly (split hand/foot malformation or lobster-claw deformity), ectodermal dysplasia, and facial clefting (cleft lip with or without cleft palate). The condition primarily affects structures derived from the ectoderm, including the skin, hair, nails, teeth, and sweat glands. EEC syndrome is most commonly caused by heterozygous mutations in the TP63 gene on chromosome 3q28, which encodes a transcription factor critical for ectodermal and limb development. The condition is also known as EEC3 (the most common form), and rarer forms have been mapped to other loci. The clinical presentation is highly variable, even within the same family. Ectrodactyly may range from mild syndactyly to severe split hand/foot deformities and can affect one or more limbs. Ectodermal dysplasia features include sparse, dry, and light-colored hair, thin and dystrophic nails, reduced sweating (hypohidrosis), and dental anomalies such as missing teeth (hypodontia) or small teeth (microdontia). Cleft lip and/or cleft palate occur in a significant proportion of affected individuals. Additional features may include lacrimal duct obstruction leading to chronic tearing and eye infections, urogenital anomalies (such as vesicoureteral reflux and hydronephrosis), conductive hearing loss, and photophobia due to blepharitis or keratitis. There is no cure for EEC syndrome, and management is multidisciplinary and symptom-based. Surgical repair of cleft lip/palate and limb malformations may be performed in infancy or childhood. Dental care, including prosthetic teeth, is often necessary. Ophthalmologic monitoring is important due to the risk of corneal complications. Dermatologic care for dry skin and management of hypohidrosis to prevent overheating are also recommended. Renal and urinary tract surveillance is advised given the risk of genitourinary anomalies. Genetic counseling is important for affected families due to the autosomal dominant inheritance pattern with variable expressivity and incomplete penetrance.

Common questions about EEC syndrome