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The skin
Published in Angus Clarke, Alex Murray, Julian Sampson, Harper's Practical Genetic Counselling, 2019
Several unusual disorders of skin pigmentation have been described that follow a patchy or whorled distribution corresponding to the lines of Blaschko, and which may be accompanied by mental retardation or other systemic features. Hypomelanosis of Ito, incontinentia pigmenti and focal dermal hypoplasia (Goltz syndrome) are the most clearly defined. Chromosomal mosaicism has been found to underlie many cases previously classed as hypomelanosis of Ito and should be sought in blood and skin biopsies or buccal cells. Recurrence risk is low unless a parent shows mosaicism. The two other conditions are caused by mutation in X-linked dominant (male lethal) genes, and the patchy skin distribution reflects the underlying pattern of X-chromosome inactivation. Somatic mutations and the heterozygous state for X-linked genes in a female both lead, functionally, to a state of mosaicism.
Genodermatoses affecting the nail
Published in Eckart Haneke, Histopathology of the NailOnychopathology, 2017
Focal dermal hypoplasia (OMIM 305600) was first described by Goltz in 1962.170 It is a rare meso-ectodermal syndrome due to a mutation of the PORCN gene mapped on chromosome Xp11.23.171PORCN encodes an enzyme that allows membrane targeting and secretion of several Wnt proteins critical for normal tissue development.172 It is lethal for hemizygous male embryos. About 10% of the patients, however, are male because males with a postzygotic new mutation or with Klinefelter syndrome can survive.173 The clinical expression is very variable and may even be hemicorporal.174–176 The developmental skin defects are characterized by widespread lesions distributed along the Blaschko lines and affecting mainly the dermis and cutaneous fat. There are also dental177 and osseous lesions, the latter being visible as striation of the long bones on X-rays.178 Multiple organ defects may be present.177,179 The skin lesions are characterized by telangiectasia, hypo- or hyperpigmentation, herniation of fatty tissue, thin hair in the affected scalp regions, and varying degree of nail hypoplasia. Nails may also be striated, ridged, dysplastic, hypoplastic, or absent.174,176
Principles of Clinical Diagnosis
Published in Susan Bayliss Mallory, Alanna Bree, Peggy Chern, Illustrated Manual of Pediatric Dermatology, 2005
Susan Bayliss Mallory, Alanna Bree, Peggy Chern
Differential diagnosisCongenital dimplesCongenital sinus tractsAplasia cutis congenitaFocal dermal hypoplasia (Goltz syndrome)
A rare form of ankyloblepharon filiforme adnatum associated with the Hay–Wells syndrome and a c.1709T>C mutation on the TP63 gene
Published in Ophthalmic Genetics, 2018
Michal Koubek, Kristýna Strakošová, Juraj Timkovič, Dagmar Grečmalová, Aneta Orlíková, Hana Burčková, Hana Wiedermannová, Petr Mašek
Due to the associated congenital defects and ectodermal developmental disorders, Hay–Wells syndrome and focal dermal hypoplasia syndrome (Goltz-Gorlin syndrome) were considered by the clinical geneticist. The combination of ankyloblepharon filiforme adnatum, ectodermal defects and palate cleft suggested Hay–Wells syndrome (OMIM 106260), also known as AEC syndrome (Ankyloblepharon ectodermal defects cleft lip/palate) as the most likely diagnosis, which was later confirmed by genetic analysis.
Clinical management of fusion in primary mandibular incisors: a systematic literature review
Published in Acta Odontologica Scandinavica, 2020
Sara Bernardi, Serena Bianchi, Guglielmo Bernardi, Jörg Philipp Tchorz, Thomas Attin, Elmar Hellwig, Lamprini Karygianni
Although the aetiological factors of the fused or double teeth are not fully understood, diverse genetic and physical forces (e.g. traumas) seem to play a fundamental role in the tooth germs fusion [5]. This clinical anomaly can be also a secondary appearance of various syndromic disorders, such as chondroectodermal dysplasia, focal dermal hypoplasia, achondrodysplasia, median cleft facial syndrome, oral-facial-digital syndrome, otodental dysplasia and Russel-Silver syndrome [10].
Hypohidrotic ectodermal dysplasia: a case report
Published in Orbit, 2020
HED is the most common type of ED, characterized by a triad of symptoms, comprising sparse hair growth (hypotrichosis), complete or partial absence of teeth (anodontia or hypodontia), and inability to sweat or diminished sweating (anhidrosis or hypohidrosis).6 HED was first reported in 1929 by Weech and is therefore known as Weech syndrome.1 Mutations in the EDA, EDAR, and DARADD genes cause HED.3,5 These genes encode a transmembrane protein, ectodysplasin-A of the tumor necrosis factor superfamily, which forms a part of the signaling pathway that is critical for the interaction between the ectoderm and mesoderm during embryogenesis.2,5 Mutations in these genes prevent normal interactions between the ectoderm and the mesoderm and normal development of the skin, hair, sweat glands, and teeth. HED is most frequently inherited in an X-linked manner, followed by an autosomal dominant or recessive pattern.2 Its prevalence is approximately 1 in every 100,000 live births.4 The disease typically manifests in men while women act as carriers. Most types of ED share common features. Ocular manifestations may vary with the type of ED. ED influences the development or function of the ocular tissues originating from the ectodermal layer; however, not all ocular tissues derived from the ectoderm are affected in all cases. The reported ocular manifestations of HED are madarosis, deficient meibomian glands, blepharitis, hypoplasia of the lacrimal glands, dry eye, entropion, ectropion, ankyloblepharon, eyelid cysts, blepharophimosis, periorbital hyperpigmentation, agenesis of the lacrimal puncta, hypoplastic NLD, dacryocystitis, strabismus, conjunctivitis, glaucoma, limbal stem cell deficiency, corneal opacity, corneal pannus, decreased corneal sensations, microphthalmia, cataract, and telecanthus.3–10 Primary acquired NLD obstruction may develop in ED because of a congenital malformation in NLD. Secondary acquired NLD obstruction in HED may develop from atrophic rhinitis, which is a common condition associated with HED.1 Similar to the ectrodactyly–ED–cleft lip/palate (EEC) syndrome, HED could be etiologically associated with syndromic congenital NLD obstruction in the present case.11,12 Dry eye and NLD obstruction may co-exist in patients with HED; therefore, DCT is a viable option in these patients. Differential diagnoses of HED include focal dermal hypoplasia, Hutchinson–Gilford progeria syndrome, Rothmund–Thomson syndrome, ichthyosis follicularis, Bowen–Armstrong syndrome, CHAND syndrome, nail dysplasia syndrome, and Johanson–Blizzard syndrome.1 There are no specific treatments for patients with HED. Genetic counseling is the central component of the preventive measures against the condition. Owing to the lack of well-defined eyebrows and eyelashes, ocular foreign bodies are common in these patients. Protective glasses with side covers are essentially helpful in preserving ocular moisture and protecting the eyes from foreign bodies. Ophthalmic management predominantly focuses on symptomatic relief of dry eye and prevention of keratopathy. Early recognition of ED may lead to more effective treatment interventions by a pediatrician, dentist, ophthalmologist, and dermatologist.5