Download Ectrodactyly-Ectodermal Dysplasia Clefting (EEC) Syndrome

National Foundation for Ectodermal Dysplasias
Ectrodactyly-Ectodermal Dysplasia Clefting
(EEC) Syndrome
One of the relatively common ectodermal dysplasia (ED) syndromes that is more complex than others is the
ectrodactyly-ectodermal dysplasia-cleft lip and palate syndrome. It is often called the EEC syndrome.
The word ectrodactyly is derived from the Greek, and means congenital absence of all or part of a finger or toe.
Both hands and both feet are usually involved, but there are exceptions and the severity of the defect is not
symmetric. Tear ducts are abnormal in most affected individuals; as a result, excessive tearing, inflammation of
the eyes, and sensitivity to light (photophobia) may occur. Skin and hair may be more lightly pigmented than
normal. Scalp hair, eyebrows, and eyelashes are sparse. Nails may be abnormal.
One of the most visible defects is cleft lip with or without cleft. The teeth may be absent or conical in shape.
Hearing loss of the conductive type has been noted. In addition, abnormal voice quality has been observed in
some individuals, and there may be defects of the reproductive organs or kidneys. Choanal atresia, recurrent
infections and growth hormone deficiency have also been reported.
In contrast to some other ectodermal dysplasia syndromes, the inheritance pattern in the EEC syndrome is
difficult to determine. In most families, only one individual is affected. In other families, autosomal dominant
inheritance seems likely; in these families affected parents have a 50% chance to pass the syndrome to their
children. Other reports in the medical literature suggest autosomal recessive inheritance; in these families
parents have a 25% chance of having another affected child. Prenatal diagnosis may be possible by transvaginal
ultrasound (looking for structural defects with a sonogram).
The gene responsible for the EEC syndrome has been identified, making it possible to confirm suspected
diagnoses and adding to the possibility for prenatal diagnosis.
Ron J. Jorgenson, DDS, PhD
Retired Clinical Geneticist,
Applied Genetics
Update 04
The content of this document is for informational purposes only. Questions regarding specific patient issues
should be directed to the appropriate professionals for resolution.