sparse eyebrows

Keratosis Follicularis Spinulosa Decalvans, AD

Clinical Characteristics
Ocular Features: 

This genodermatosis has signs and symptoms beginning in childhood.  Photophobia is a prominent symptom.  The eyebrows and eyelashes are thin and sparse.  Recurrent blepharitis and keratitis are often present.

Systemic Features: 

The scalp is often dry and scaly.  Scalp alopecia begins sometime in the first two decades of life and becomes a major complaint by the third or fourth decade.  The face and especially the cheeks are often erythematous.  The scalp can have multiple follicular pustules which are most prominent in the occipital and nuchal areas.  Follicular keratotic papules are often located on the trunk and extensor areas of the limbs.  Histology of scalp skin biopsies show epidermal hyperplasia and an extensive perifollicular inflammatory infiltrate.

Enamel hypoplasia result in multiple and recurrent caries and loss of teeth.  The nails are often dystrophic.

Genetics

This is likely an autosomal dominant disorder based on the transmission pattern of several reported families but no locus or mutation has been reported.

There is also an X-linked form of Keratosis Follicularis Spinulosa Decalvans (KFSDX) (308800) which is more common.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Dental surveillance and treatment are important.  Ocular lubrication can be helpful in severe cases and ophthalmic topical antibiotics may be useful in treatment of blepharitis and keratitis.Clinica

References
Article Title: 

Gabriele-de Vries Syndrome

Clinical Characteristics
Ocular Features: 

A number of nondiagnostic signs occur in the periocular structures as part of the general facial dysmorphism.  There is a general fullness to the periocular area, most evident in the upper eyelids.  The lid fissures slant downward and the eyebrows are sparse.  Strabismus is often present.  Ptosis has been noted in a few individuals.

Systemic Features: 

Systemic signs are inconsistent and highly variable.  Intrauterine growth is usually below average.  Feeding problems are evident from birth.  The facial dysmorphology is highlighted by a high, broad forehead and accentuated by micrognathia and midface hypoplasia.  The ears are posteriorly rotated.  General development is delayed and milestones, if achieved, are delayed.  Behavioral problems can be manifest as anxiety and some individuals have features of the autism spectrum.  Abnormal movements such as tremor and dystonia are sometimes present.

Brain imaging may reveal delayed myelination, frontal gliosis, white matter abnormalities, and enlarged ventricles.

Genetics

Heterozygous mutations in the YY1 gene (14q32) have been identified in this condition.  The gene is a transcription factor that acts both as a repressor and an activator in specific circumstances.  Virtually all cases occur de novo.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

No effective generalized treatment has been reported.

References
Article Title: 

YY1 Haploinsufficiency Causes an Intellectual Disability Syndrome Featuring Transcriptional and Chromatin Dysfunction

Gabriele M, Vulto-van Silfhout AT, Germain PL, Vitriolo A, Kumar R, Douglas E, Haan E, Kosaki K, Takenouchi T, Rauch A, Steindl K, Frengen E, Misceo D, Pedurupillay CRJ, Stromme P, Rosenfeld JA, Shao Y, Craigen WJ, Schaaf CP, Rodriguez-Buritica D, Farach L, Friedman J, Thulin P, McLean SD, Nugent KM, Morton J, Nicholl J, Andrieux J, Stray-Pedersen A, Chambon P, Patrier S, Lynch SA, Kjaergaard S, Torring PM, Brasch-Andersen C, Ronan A, van Haeringen A, Anderson PJ, Powis Z, Brunner HG, Pfundt R, Schuurs-Hoeijmakers JHM, van Bon BWM, Lelieveld S, Gilissen C, Nillesen WM, Vissers LELM, Gecz J, Koolen DA, Testa G, de Vries BBA. YY1 Haploinsufficiency Causes an Intellectual Disability Syndrome Featuring Transcriptional and Chromatin Dysfunction. Am J Hum Genet. 2017 Jun 1;100(6):907-925.

PubMed ID: 
28575647

Encephalopathy, Early-Onset, With Brain Atrophy and Thin Corpus Callosum

Clinical Characteristics
Ocular Features: 

Optic atrophy is present in many patients and may be present early since lack of visual tracking or eye contact may be noted at birth.  Sparse eyebrows, upslanting palpebral fissures, and hypertelorism have also been reported.

Systemic Features: 

Severe hypotonia is present at birth often causing respiratory distress in the neonate.  Spasticity can develop later.  Growth failure with progressive microcephaly is present in infants.  Brain imaging often reveals diffuse atrophy of structures including the cerebellum, brainstem, spinal cord, and cerebrum.  Tongue fasciculations have been observed.   Micrognathia and widely spaced teeth are sometimes present.  Several patients have died during infancy.

Genetics

Homozygous mutations in the TBCD (17q25.3) are responsible for this disorder.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

No treatment has been reported.

References
Article Title: 

Biallelic Mutations in TBCD, Encoding the Tubulin Folding Cofactor D, Perturb Microtubule Dynamics and Cause Early-Onset Encephalopathy

Flex E, Niceta M, Cecchetti S, Thiffault I, Au MG, Capuano A, Piermarini E, Ivanova AA, Francis JW, Chillemi G, Chandramouli B, Carpentieri G, Haaxma CA, Ciolfi A, Pizzi S, Douglas GV, Levine K, Sferra A, Dentici ML, Pfundt RR, Le Pichon JB, Farrow E, Baas F, Piemonte F, Dallapiccola B, Graham JM Jr, Saunders CJ, Bertini E, Kahn RA, Koolen DA, Tartaglia M. Biallelic Mutations in TBCD, Encoding the Tubulin Folding Cofactor D, Perturb Microtubule Dynamics and Cause Early-Onset Encephalopathy. Am J Hum Genet. 2016 Oct 6;99(4):962-973.

PubMed ID: 
27666370

Biallelic TBCD Mutations Cause Early-Onset Neurodegenerative Encephalopathy

Miyake N, Fukai R, Ohba C, Chihara T, Miura M, Shimizu H, Kakita A, Imagawa E, Shiina M, Ogata K, Okuno-Yuguchi J, Fueki N, Ogiso Y, Suzumura H, Watabe Y, Imataka G, Leong HY, Fattal-Valevski A, Kramer U, Miyatake S, Kato M, Okamoto N, Sato Y, Mitsuhashi S, Nishino I, Kaneko N, Nishiyama A, Tamura T, Mizuguchi T, Nakashima M, Tanaka F, Saitsu H, Matsumoto N. Biallelic TBCD Mutations Cause Early-Onset Neurodegenerative Encephalopathy. Am J Hum Genet. 2016 Oct 6;99(4):950-961.

PubMed ID: 
27666374

Mandibulofacial Dysostosis with Alopecia

Clinical Characteristics
Ocular Features: 

The extensive dysplasia of the facial bones involves those of the orbital rims and zygomatic arches.  The orbital rims can be malformed and there is often a broad depression at the inferolateral region of the eyes.  Hypoplasia or even aplasia of the eyelids maybe present and some individuals have colobomas of the lower eyelids.  The lacrimal punctae may be temporally displaced.  The eyebrows and eyelashes are often sparse as part of the generalized alopecia.

Systemic Features: 

This is a disorder of craniofacial development resulting in extensive malformations of facial bones and skin.  Different rates of development among these structures leads to facial asymmetry in many patients. Maxillary, zygomatic arch, and mandibular bones are dysplastic resulting in micrognathia and a flat midface.   The temporomandibular joints are absent and the external ear canals are often incompletely formed.  Conductive hearing loss is common with hypoplastic ossicular chains while the pinnae are low-set, crumpled and abnormally cupped.  There may be preauricular tags or pits present.  Tooth eruption is often delayed and there may be agenesis of many permanent teeth.  The maxillary sinuses may be absent.  Cleft palate is often present.

Genetics

Heterozygous mutations in the EDNRA gene (4q31) are responsible for this condition.  No familial cases have been reported and it can be assumed that the mutations arise de novo. 

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

There is no treatment for the overall condition but individual anomalies such as the colobomas, dental deformities and cleft palate may be surgically repaired.  Upper airway obstruction may require tracheostomy in infants.

References
Article Title: 

Mutations in the endothelin receptor type A cause mandibulofacial dysostosis with alopecia

Gordon CT, Weaver KN, Zechi-Ceide RM, Madsen EC, Tavares AL, Oufadem M, Kurihara Y, Adameyko I, Picard A, Breton S, Pierrot S, Biosse-Duplan M, Voisin N, Masson C, Bole-Feysot C, Nitschke P, Delrue MA, Lacombe D, Guion-Almeida ML, Moura PP, Garib DG, Munnich A, Ernfors P, Hufnagel RB, Hopkin RJ, Kurihara H, Saal HM, Weaver DD, Katsanis N, Lyonnet S, Golzio C, Clouthier DE, Amiel J. Mutations in the endothelin receptor type A cause mandibulofacial dysostosis with alopecia. Am J Hum Genet. 2015 Apr 2;96(4):519-31.

PubMed ID: 
25772936

Hypotrichosis-Lymphedema-Telangiectasia-Renal Defect Syndrome

Clinical Characteristics
Ocular Features: 

Sparse hair can be noted at birth and by several years of age the alopecia of the eyelids and eyebrows is complete.  The upper eyelids may be swollen at birth as well. 

Systemic Features: 

The facial features are unusual.  The nose appears long and may have a broad nasal root.  The lips are full and the lower jaw is prominent. Evidence of developmental delay has been reported in one patient.

The scrotum can be edematous at birth and sometimes contains large hydroceles.  Hair is sparse in infancy but within a few years alopecia is complete.  Telangiectases on the scalp, scrotum, and limbs are evident at several years of age.  Pulmonary vascular congestion and lymphangiectasia may be present in some individuals antenatally.  Renal failure, sometimes with hypertension can occur at any time from early childhood to young adulthood.  Renal biopsy has shown histologic features consistent with membranoproliferative glomerulonephritis and thrombotic microangiopathy.  This may be preceded by proteinuria in infants as young as 2 years. 

Genetics

This condition is the result of heterozygous mutations in the SOX18 gene (20q13.33). 

Homozygous mutations in the same gene may be responsible for a somewhat similar disorder (HLTS) (607823) which has many of the same facial and systemic features but lacks the renal disease. 

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Some patients have benefitted from renal transplantation.

References
Article Title: 

Basel-Vanagaite-Smirin-Yosef Syndrome

Clinical Characteristics
Ocular Features: 

The eyes appear abnormally far apart.  Ptosis, microcornea, congenital cataracts, sparse eyebrows, and strabismus are usually present.  Epicanthal folds are often seen.

Systemic Features: 

Psychomotor development is severely delayed and with delay or absence of milestones.  DTRs are often hyperactive but some infants are described as hypotonic.  Some individuals have seizures.  There may be a nevus flammeus simplex lesion on the forehead and body hair is sparse.  Cleft palate, cardiac septal defects, hypospadius, thin corpus callosum and cerebral ventricular dilation have been observed.  The upper lip may have a tented morphology with everted lower lip vermilion. A short philtrum is common. 

Genetics

A homozygous missense mutation in the MED25 gene (19q13.33) has been reported and the transmission pattern is consistent with autosomal recessive inheritance.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

No known treatment has been reported.

References
Article Title: 

Homozygous MED25 mutation implicated in eye-intellectual disability syndrome

Basel-Vanagaite L, Smirin-Yosef P, Essakow JL, Tzur S, Lagovsky I, Maya I, Pasmanik-Chor M, Yeheskel A, Konen O, Orenstein N, Weisz Hubshman M, Drasinover V, Magal N, Peretz Amit G, Zalzstein Y, Zeharia A, Shohat M, Straussberg R, Monte D, Salmon-Divon M, Behar DM. Homozygous MED25 mutation implicated in eye-intellectual disability syndrome. Hum Genet. 2015 Jun;134(6):577-87.

PubMed ID: 
25792360

Barber-Say Syndrome

Clinical Characteristics
Ocular Features: 

The ocular features consist mainly of skin changes in the lids including hyperlaxity and redundancy.  There may be ectropion of the lower eyelids and sparsity of the eyebrows.  Some evidence of micro- or ablepharon is often present.  Hypertelorism and exophthalmia have been described.

Systemic Features: 

Multiple external congenital anomalies are present at birth including skin laxity, hypertrichosis (especially of the forehead, neck and back), and low-set and malformed pinnae.  Macrostomia and thin lips with redundant facial skin are often evident.  The nose appears bulbous.  The thoracic skin can be atrophic and the nipples may be hypoplastic.  Hypospadias has been reported.  A highly arched or cleft palate may be present and some individuals have a conductive hearing loss.  The teeth are small and eruption may be delayed.  Cognitive deficits may be present and mental retardation has been reported. 

Genetics

Based on genotyping and the limited number of reported pedigrees, inheritance most likely follows an autosomal dominant pattern.  Direct parent to child transmission has been reported.  Detailed examination of parents sometimes reveals mild features that are easily missed.  Mutations in the TWIST2 gene have been found in 10 unrelated individuals with Barber-Say syndrome.

TWIST2 mutations have also been found in Setleis syndrome (227260) and in ablepharon-macrostomia syndrome (200110).  These conditions have some clinical features in common with Barber-Say syndrome.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

There is no known treatment for this disorder but correction of selected anomalies such as ectropion and cleft palate may be indicated.

References
Article Title: 

Recurrent Mutations in the Basic Domain of TWIST2 Cause Ablepharon Macrostomia and Barber-Say Syndromes

Marchegiani S, Davis T, Tessadori F, van Haaften G, Brancati F, Hoischen A, Huang H, Valkanas E, Pusey B, Schanze D, Venselaar H, Vulto-van Silfhout AT, Wolfe LA, Tifft CJ, Zerfas PM, Zambruno G, Kariminejad A, Sabbagh-Kermani F, Lee J, Tsokos MG, Lee CC, Ferraz V, da Silva EM, Stevens CA, Roche N, Bartsch O, Farndon P, Bermejo-Sanchez E, Brooks BP, Maduro V, Dallapiccola B, Ramos FJ, Chung HY, Le Caignec C, Martins F, Jacyk WK, Mazzanti L, Brunner HG, Bakkers J, Lin S, Malicdan MC, Boerkoel CF, Gahl WA, de Vries BB, van Haelst MM, Zenker M, Markello TC. Recurrent Mutations in the Basic Domain of TWIST2 Cause Ablepharon Macrostomia and Barber-Say Syndromes. Am J Hum Genet. 2015 Jul 2;97(1):99-110.

PubMed ID: 
26119818

Kaufman Oculocerebrofacial Syndrome

Clinical Characteristics
Ocular Features: 

Alterations in the morphology of periocular structures is the most consistent ocular feature.  These include epicanthal folds, upward-slanting lid fissures, ptosis, blepharophimosis, sparse eyebrows, and telecanthus.  However, pale optic discs, iris colobomas, microcornea, strabismus, nystagmus, and hypertelorism are variably present. 

Systemic Features: 

There is both intrauterine and postnatal growth retardation.  Hypotonia is often noted along with general psychomotor delays.  Neonatal respiratory distress and laryngeal stridor may be present.  The intellectual disability can be severe.  Corpus callosum aplasia and hypoplasia have been reported.  Microcephaly and brachycephaly with delayed suture closure are features.  The face is long and narrow and the mouth is disproportionally large.  A high arched palate can be present and the pinnae are often deformed, posteriorly rotated and may be accompanied by preauricular skin tags. The teeth appear widely spaced (diastema) and the lower jaw is underdeveloped.

Genetics

Kaufman BPIDS syndrome results from homozygous or compound heterozygous mutations in the UBE3B gene (12q23).

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

No general treatment is available although repair of some specific malformations is possible.

References
Article Title: 

Deficiency for the ubiquitin ligase UBE3B in a blepharophimosis-ptosis-intellectual-disability syndrome

Basel-Vanagaite L, Dallapiccola B, Ramirez-Solis R, Segref A, Thiele H, Edwards A, Arends MJ, Miro X, White JK, Desir J, Abramowicz M, Dentici ML, Lepri F, Hofmann K, Har-Zahav A, Ryder E, Karp NA, Estabel J, Gerdin AK, Podrini C, Ingham NJ, Altmuller J, Nurnberg G, Frommolt P, Abdelhak S, Pasmanik-Chor M, Konen O, Kelley RI, Shohat M, Nurnberg P, Flint J, Steel KP, Hoppe T, Kubisch C, Adams DJ, Borck G. Deficiency for the ubiquitin ligase UBE3B in a blepharophimosis-ptosis-intellectual-disability syndrome. Am J Hum Genet. 2012 Dec 7;91(6):998-1010.

PubMed ID: 
23200864

An oculocerebrofacial syndrome

Kaufman RL, Rimoin DL, Prensky AL, Sly WS. An oculocerebrofacial syndrome. Birth Defects Orig Artic Ser. 1971 Feb;7(1):135-8.

PubMed ID: 
5006210

Palmoplantar Keratoderma and Woolly Hair

Clinical Characteristics
Ocular Features: 

Eyebrows and eyelashes are sparse.

Systemic Features: 

Striate palmoplantar keratoderma, more pronounced in the soles, with leukonychia are present.  Scalp and body hair are sparse.  Woolly hair is present in some patients.  The toes may be somewhat rotated with a bulbous appearance distally.  Older individuals have more marked skin changes suggesting some progression.

Genetics

This autosomal recessive condition is the result of homozygous missense mutations in the KANK2 gene (19p13.2).  Eight patients in two families of Arab descent have been reported.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

No treatment is known.

References
Article Title: 

Mowat-Wilson Syndrome

Clinical Characteristics
Ocular Features: 

Most reports of Mowat-Wilson disorders provide only incomplete ocular findings and the full phenotype remains to be described.  Most of the reported findings are part of the facial phenotype, such as downward slanting palpebral fissures, and 'wedge-shaped' eyebrows with the medial portion visibly wider than the temporal region.  Hypertelorism, strabismus and telecanthus have also been noted.  However, optic nerve atrophyor aplasia, RPE atrophy, microphthalmia, ptosis, and cataracts are sometimes present while strabismus is more common.  Iris and other uveal colobomas may be present and at least one patient has been reported with retinal aplasia.  There may be considerable asymmetry in the features among the two eyes.

Systemic Features: 

This is a highly complex dysmorphic developmental disorder with unusual progression of facial features.  Birth weight and length are usually normal but later there is general somatic and mental growth delay with microcephaly (pre- and post natal), short stature, intellectual disability, and epilepsy (70%).  Hypotonia has been noted at birth.  A significant proportion (~50%) of patients have Hirschsprung disease with megacolon.  Congenital heart defects are common, many involving septal openings.  Hypospadias is often present with or without other genitourinary anomalies.  Teeth are often crowded and crooked.  The earlobes may be flattened and may have a central depression.

The facial features are present in early childhood but as they mature the upper half of the nasal profile becomes convex, while the nasal tip becomes longer and overhangs the philtrum.  The eyes appear more deeply set.  The chin lengthens and prognathism becomes apparent.  IQ levels cannot be determined but many individuals exhibit behavioral or emotional disturbances.

Genetics

Heterozygous mutations in ZEB2 (2q22.3) are responsible for most cases (81%) of this disorder.  A large number of molecular mutations, many of the nonsense type, have been reported. About 2-4% of patients have cytogenetic alterations involving the 2q22 region.

Another disorder with microcephaly, intellectual disability and Hirschsprung disease is Goldberg-Shprintzen syndrome (609460) with mutations in the KIAA1279 gene.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Treatment may be directed at specific defects but there is no treatment for the general disorder. Individuals can live to adulthood. Treatment is largely symptomatic.  Physical and speech treatment can be helpful if initiated early.

References
Article Title: 

Phenotype and genotype of 87 patients with Mowat-Wilson syndrome and

Ivanovski I, Djuric O, Caraffi SG, Santodirocco D, Pollazzon M, Rosato S,
Cordelli DM, Abdalla E, Accorsi P, Adam MP, Ajmone PF, Badura-Stronka M, Baldo C,
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Cuturilo G, De Brasi D, Devriendt K, Dinulos MB, Hjortshoj TD, Epifanio R,
Faravelli F, Fiumara A, Formisano D, Giordano L, Grasso M, Gronborg S, Iodice A,
Iughetti L, Kuburovic V, Kutkowska-Kazmierczak A, Lacombe D, Lo Rizzo C, Luchetti
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Nielsen JEK, Obersztyn E, Pantaleoni C, Pellicciari A, Pisanti MA, Prpic I,
Poch-Olive ML, Raviglione F, Renieri A, Ricci E, Rivieri F, Santen GW, Savasta S,
Scarano G, Schanze I, Selicorni A, Silengo M, Smigiel R, Spaccini L, Sorge G,
Szczaluba K, Tarani L, Tone LG, Toutain A, Trimouille A, Valera ET, Vergano SS,
Zanotta N, Zenker M, Conidi A, Zollino M, Rauch A, Zweier C, Garavelli L.
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PubMed ID: 
29300384

Clinical spectrum of eye malformations in four patients with Mowat-Wilson syndrome

Bourchany A, Giurgea I, Thevenon J, Goldenberg A, Morin G, Bremond-Gignac D, Paillot C, Lafontaine PO, Thouvenin D, Massy J, Duncombe A, Thauvin-Robinet C, Masurel-Paulet A, Chehadeh SE, Huet F, Bron A, Creuzot-Garcher C, Lyonnet S, Faivre L. Clinical spectrum of eye malformations in four patients with Mowat-Wilson syndrome. Am J Med Genet A. 2015 Apr 21. [Epub ahead of print]

PubMed ID: 
25899569

The behavioral phenotype of Mowat-Wilson syndrome

Evans E, Einfeld S, Mowat D, Taffe J, Tonge B, Wilson M. The behavioral phenotype of Mowat-Wilson syndrome. Am J Med Genet A. 2012 Feb;158A(2):358-66. doi: 10.1002/ajmg.a.34405.

PubMed ID: 
22246645

Mowat-Wilson syndrome: facial phenotype changing with age: study of 19 Italian patients and review of the literature

Garavelli L, Zollino M, Mainardi PC, Gurrieri F, Rivieri F, Soli F, Verri R, Albertini E, Favaron E, Zignani M, Orteschi D, Bianchi P, Faravelli F, Forzano F, Seri M, Wischmeijer A, Turchetti D, Pompilii E, Gnoli M, Cocchi G, Mazzanti L, Bergamaschi R, De Brasi D, Sperandeo MP, Mari F, Uliana V, Mostardini R, Cecconi M, Grasso M, Sassi S, Sebastio G, Renieri A, Silengo M, Bernasconi S, Wakamatsu N, Neri G. Mowat-Wilson syndrome: facial phenotype changing with age: study of 19 Italian patients and review of the literature. Am J Med Genet A. 2009 Mar;149A(3):417-26. Review.

PubMed ID: 
19215041

Clinical and mutational spectrum of Mowat-Wilson syndrome

Zweier C, Thiel CT, Dufke A, Crow YJ, Meinecke P, Suri M, Ala-Mello S, Beemer F, Bernasconi S, Bianchi P, Bier A, Devriendt K, Dimitrov B, Firth H, Gallagher RC, Garavelli L, Gillessen-Kaesbach G, Hudgins L, K?SS?SSri?SSinen H, Karstens S, Krantz I, Mannhardt A, Medne L, M?ocke J, Kibaek M, Krogh LN, Peippo M, Rittinger O, Schulz S, Schelley SL, Temple IK, Dennis NR, Van der Knaap MS, Wheeler P, Yerushalmi B, Zenker M, Seidel H, Lachmeijer A, Prescott T, Kraus C, Lowry RB, Rauch A. Clinical and mutational spectrum of Mowat-Wilson syndrome. Eur J Med Genet. 2005 Apr-Jun;48(2):97-111

PubMed ID: 
16053902
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