Ectrodactyly-Ectodermal Dysplasia-Clefting Syndrome (EEC)
EEC syndrome, there are three different forms of EEC: EEC type 1, 2 and 3. Only one family has been identified with EEC 1 and 2. The most common type is EEC 3.
Ectrodactyly ectodermal dysplasia cleft lip/palate (EEC) syndrome is a rare genetic disorder. Symptoms can vary greatly from one person to another. Affected individuals often have abnormalities affecting the limbs, including ectrodactyly, a condition in which part or all of the central digits (fingers or toes) are missing. Ectrodactyly often affects the middle fingers or toes, but can present differently in different people (or be absent altogether). A groove or gap in the upper lip (cleft lip) and a groove or gap in the roof of the mouth (cleft palate) may also occur. The ectodermal dysplasia component refers to abnormalities to structures that arise from the outermost layer of the embryo (ectoderm). In EEC syndrome, this generally affects the hair, teeth, nails, skin and sweat glands. Individuals with EEC syndrome can also develop a variety of additional symptoms, including abnormalities of the genitourinary system and the eyes. Intelligence does not seem to be affected. Most cases of EEC syndrome are caused by mutations of the TP63 gene and are either new (spontaneous) mutations or are inherited as autosomal dominant disorders.
1 in 20,000 births.
Spectrum of hand and foot defects with missing digits, median cleft and fusion of the remaining digits resulting in clawlike extremities.
Chromosomal abnormalities: Found in trisomy 18.
High incidence of genetic syndromes, the most common are:
Autosomal recessive; ectrodactyly, phocomelia, facial cleft.
Ectrodactyly – ectodermal dysplasia (EEC):
Autosomal dominant; deferomities of all four extremities, but more severe in the hands, and ectodermal defects (dry skin, sparse hair, dental defects and defects of the tear ducts).
Autosomal dominant but in most cases de novo mutations; ectrodactyly, micrognathia, external ear anomalies.
Split hand and foot malformation:
Ectrodactyly presenting as ‘lobster claw’ anomaly.