microcephaly

Baraitser-Winter Syndrome 1

Clinical Characteristics
Ocular Features: 

Ptosis (both unilateral and bilateral), hypertelorism, prominent epicanthal folds, and colobomata are common.  The iris stroma may be dysplastic and correctopia has been observed.  Visual acuity has not been measured.

Systemic Features: 

Postnatal growth retardation leads to short stature.  Microcephaly and morphological aberrations in the brain such as lissencephaly, agenesis of the corpus callosum and pachygyria are present.  Seizures and developmental delays are common.  Hearing loss is sensorineural in type.

The ears are low-set and the posterior hair line may be low as well.  The nasal bridge appears broad and the nose appears short. Male genitalia are often underdeveloped.  Bicuspid aortic valves, patent ductus arteriosus, and aortic stenosis have been reported.

Genetics

Heterozygous mutations in the ACTB gene (7p22.1) are responsible for this apparent autosomal dominant syndrome.  However, all patients have been sporadic.

This condition is clinically similar to Baraitser-Winter syndrome 2 (614583) which is a unique entity caused by a mutation in ACTG1

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

No specific treatment is available.

References
Article Title: 

New ocular finding in Baraitser-Winter syndrome

Rall N, Leon A, Gomez R, Daroca J, Lacassie Y. New ocular finding in Baraitser-Winter syndrome. Eur J Med Genet. 2017 Oct 9. pii: S1769-7212(17)30156-8. doi: 10.1016/j.ejmg.2017.10.006. [Epub ahead of print].

PubMed ID: 
29024830

Baraitser-Winter cerebrofrontofacial syndrome: delineation of the spectrum in 42 cases

Verloes A, Di Donato N, Masliah-Planchon J, Jongmans M, Abdul-Raman OA, Albrecht B, Allanson J, Brunner H, Bertola D, Chassaing N, David A, Devriendt K, Eftekhari P, Drouin-Garraud V, Faravelli F, Faivre L, Giuliano F, Guion Almeida L, Juncos J, Kempers M, Eker HK, Lacombe D, Lin A, Mancini G, Melis D, Lourenco CM, Siu VM, Morin G, Nezarati M, Nowaczyk MJ, Ramer JC, Osimani S, Philip N, Pierpont ME, Procaccio V, Roseli ZS, Rossi M, Rusu C, Sznajer Y, Templin L, Uliana V, Klaus M, Van Bon B, Van Ravenswaaij C, Wainer B, Fry AE, Rump A, Hoischen A, Drunat S, Riviere JB, Dobyns WB, Pilz DT. Baraitser-Winter cerebrofrontofacial syndrome: delineation of the spectrum in 42 cases. Eur J Hum Genet. 2014 Jul 23.

PubMed ID: 
25052316

De novo mutations in the actin genes ACTB and ACTG1 cause Baraitser-Winter syndrome

Riviere JB, van Bon BW, Hoischen A, Kholmanskikh SS, O'Roak BJ, Gilissen C, Gijsen S, Sullivan CT, Christian SL, Abdul-Rahman OA, Atkin JF, Chassaing N, Drouin-Garraud V, Fry AE, Fryns JP, Gripp KW, Kempers M, Kleefstra T, Mancini GM, Nowaczyk MJ, van Ravenswaaij-Arts CM, Roscioli T, Marble M, Rosenfeld JA, Siu VM, de Vries BB, Shendure J, Verloes A, Veltman JA, Brunner HG, Ross ME, Pilz DT, Dobyns WB. De novo mutations in the actin genes ACTB and ACTG1 cause Baraitser-Winter syndrome. Nat Genet. 2012 Feb 26;44(4):440-4.

PubMed ID: 
22366783

Feingold Syndrome 1

Clinical Characteristics
Ocular Features: 

Short, narrow palpebral fissures have been reported (73%).  The fissures may be up slanting and epicanthal folds have been noted.   

Systemic Features: 

The face can appear asymmetrical and triangular and the head is small in 89% of individuals.  Micrognathia is usually present and the lips appear full.  The nasal bridge is broad and the nostrils are anteverted.  The ears are often low-set and rotated posteriorly.  Syndactyly of the toes is common (97%) and the fingers are often anomalous (particularly 5th finger clinodactyly and brachydactyly) with hypoplastic thumbs.  Shortening of the 2nd and 5th middle phalanx of the fingers is especially common.  True short stature is uncommon but 60% are below the 10th centile.  Rare individuals have a sensorineural hearing loss.

Tracheoesophageal fistulas are often present, together with atresia of the duodenum and sometimes the esophagus as well.  Cardiac, renal, and vertebral malformations are seen in a minority of patients.

Intelligence may be normal but more often is below average and learning difficulties are often present.

Genetics

This is an autosomal dominant disorder secondary to mutations in the MYCN gene (2p24.3).

MYCN is up regulated in some patients with retinoblastoma (180200).

Feingold syndrome 2 (614326) is caused by hemizygous deletions of the MIR17HG gene but no ocular signs have been reported.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

There is no known treatment for the syndrome but surgery can be important for some of the external and internal malformations. Special education and treatment of hearing loss are important.

References
Article Title: 

Genotype-phenotype correlations in MYCN-related Feingold syndrome

Marcelis CL, Hol FA, Graham GE, Rieu PN, Kellermayer R, Meijer RP, Lugtenberg D, Scheffer H, van Bokhoven H, Brunner HG, de Brouwer AP. Genotype-phenotype correlations in MYCN-related Feingold syndrome. Hum Mutat. 2008 Sep;29(9):1125-32.

PubMed ID: 
18470948

Orofaciodigital Syndrome IX

Clinical Characteristics
Ocular Features: 

Multiple forms of orofaciodigital syndrome are recognized but this one (type IX, originally reported as VIII) is of ophthalmological interest because of the retinal anomalies.  Gurrieri’s original report calls these “retinochoroideal lacunae of colobomatous origin” similar to those found in Aicardi syndrome (304050).  These were further described as hypopigmented and atrophic appearing.  Synophyrs and hypertelorism have been noted and the ears may be low-set.

Systemic Features: 

Facial, oral, digital, psychomotor delays, and skeletal anomalies are major systemic features of OFD IX.  The oral manifestations include a high arched palate, cleft lip (sometimes subtle), bifid tongue, hemartomas on the tongue, abnormal tongue frenulation, and dental anomalies (supernumerary teeth).  Digital anomalies consist of mild syndactyly and occasionally polydactyly, brachydactyly, and bifid large toes.  Some patients have short stature.  Psychomotor delay is common and some patients have been described as mentally retarded.

Genetics

This is most likely an autosomal recessive condition since multiple sibs of both sexes have been identified.  Nothing is known of the locus or specific mutation.

Gurrieri’s name is attached to another syndrome (Gurrieri syndrome [601187]) with entirely different oculoskeletal features.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

Specific malformations may need correction but there is no treatment for the overall disease.

References
Article Title: 

Hoyeraal-Hreidarsson Syndrome

Clinical Characteristics
Ocular Features: 

Little is known about the ocular signs in this rare disorder.  As many patients have systemic features of dyskeratosis congenita, however, it is possible that some of the ocular findings such as conjunctival and corneal scarring and lid margin distortion might be similar.  Hoyeraal-Hreidarsson syndrome, though, is a more severe disease and many infants may die before the mucocutaneous manifestations appear.  At least one patient has had an exudative retinopathy similar to that seen in Revesz syndrome (268130).  Epiphora and a preretinal hemorrhage have also been reported.

Systemic Features: 

Features of pancytopenia usually appear after 5 months of age while growth retardation and microcephaly are evident soon after birth.  The marrow may show progression to myelodysplasia.  Birth weight is usually low.  Truncal ataxia and axial hypotonia have been reported and MRI imaging reveals cerebellar hypoplasia.  Global developmental delay is a common feature and a few patients have seizures.  Susceptibility to infection has been noted but the basis for an immunodeficiency remains elusive.  Some patients have signs of dyskeratosis congenita such as sparse hair, nail dysplasia, and a reticular pattern of skin pigmentation.

Genetics

This is an X-linked disorder resulting from mutations in the DKC1 gene (Xq28) active in telomere maintainence.  As expected, the vast majority of affected individuals are male but at least 3 females have been reported. The same gene is also mutated in the X-linked form of dyskeratosis congenita (305000) suggesting that the two are allelic or that both are the same disease.  There are clear clinical differences, however, as severe developmental delay, immunodeficiency, cerebellar hypoplasia, and microcephaly are generally not present in the latter disorder.

There is evidence for telomere length variations in this syndrome and in dyskeratosis congenita.  Homozygous mutations in RTEL1 (regulator of telomere length helicase 1) (20q13.33) have also been found in these conditions.

Pedigree: 
X-linked recessive, carrier mother
X-linked recessive, father affected
Treatment
Treatment Options: 

No effective treatment has been reported.

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,
Baldi M, Bayat A, Bigoni S, Bonvicini F, Breckpot J, Callewaert B, Cocchi G,
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
A, Malbora B, Mammi I, Mari F, Montorsi G, Moutton S, Moller RS, Muschke P,
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.
Phenotype and genotype of 87 patients with Mowat-Wilson syndrome and
recommendations for care
. Genet Med. 2018 Jan 4. doi: 10.1038/gim.2017.221. [Epub
ahead of print].

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

Congenital Disorder of Glycosylation, Type Ij

Clinical Characteristics
Ocular Features: 

Bilateral cataracts are present at birth.  Nystagmus, strabismus, and long eyelashes have been reported.

Systemic Features: 

This is a disorder of glycosylation important to the formation of glycoproteins and glycolipids.  Neurological signs such as tremor, clonus, and muscle fasiculations may be seen soon after birth.  Other neurological abnormalities eventually include psychomotor retardation, seizures, mental retardation, hyperexcitabilty, and ataxia.  Failure to thrive and feeding difficulties are evident early.  Progressive microcephaly is a feature.  Liver dysfunction can lead to coagulopathy and hypoproteinemia with hepatomegaly is sometimes present.  Some patients have facial anomalies, inverted nipples, and subcutaneous fat pads.  The MRI may show areas of brain atrophy, ischemia, and focal necrosis.

Longevity is limited with 2 of 3 reported patients dying within 2 years of life.

Genetics

This is a rare autosomal recessive disorder resulting from mutations in DPAGT1 (11q23.3) resulting in defective N-glycosylation.  There are numerous other types of glycosylation defects with variations in the clinical manifestations.

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

Treatment consists of fluid and caloric intake management.  Hypoproteinemia and coagulation defects may respond to oral mannose administration.

References
Article Title: 

Retinitis Pigmentosa and Mental Retardation

Clinical Characteristics
Ocular Features: 

The lenses may have pleomorphic white axial opacities but in other patients can be totally opacified.  Optic atrophy is present and vision may be reduced to light perception but nystagmus is absent.  Evidence suggests that vision loss is progressive.  Some patients have extensive posterior synechiae while others have been noted to have sluggish pupils.  High myopia is a feature. The retinal pigmentation has a typical retinitis pigmentosa picture with attenuated retinal vessels and equatorial bone spicule pigmentation located in the midperiphery while the macula can have a bull’s eye appearance.   

Systemic Features: 

Early development may seem normal but developmental milestones are usually delayed.  Postnatal microcephaly and growth deficiency with mental retardation and early hypotonia are typical features.  The mental retardation may be severe.  Scoliosis and arachnodactyly have been noted and hypogonadism has been reported.  Speech may not develop and mobility is sometimes limited.

Genetics

The family pattern suggests autosomal recessive inheritance.  Homozygosity mapping has identified in a region of chromosome 8 (8q21.2-22.1) that overlaps the region for Cohen syndrome () but no specific mutated gene has been identified.      

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

None.

References
Article Title: 

Leukoencephalopathy with Vanishing White Matter

Clinical Characteristics
Ocular Features: 

Optic atrophy is a common feature and blindness is often the result.

Systemic Features: 

Onset of symptoms may occur at any time from 1.5 years of age to adulthood.  Early psychomotor development may be normal but developmental milestones such as walking and crawling are often delayed.  Patients with a later onset often have a milder course.  Progression is chronic but often episodic with exacerbations following infection and blunt head trauma. Mental stress, even of a relatively minor nature such as fright, may likewise cause a worsening of symptoms.  Such episodes can lead to loss of consciousness or even coma.  Cerebellar ataxia and spasticity are common.  Epilepsy may occur but is uncommon.  Motor function is more severely impaired compared with mental deterioration.  The MRI reveals a diffuse leukoencephalopathy as well as focal and cystic degeneration of white matter which may be present before the onset of symptoms.  Cerebellar atrophy primarily involving the vermis is common.  Behavioral problems, psychiatric symptoms, and even signs of dementia have been reported.  The vast majority of patients have cognitive disabilities and many become severely handicapped and immobile.  Early onset disease in children often leads to death within a few years whereas adults with later onset may live for many years.       

Females with leukoencephalopathy who live to puberty may experience ovarian failure, a condition sometimes called ovarioleukodystrophy.

Genetics

This is an autosomal recessive disorder secondary to homozygous mutations in one of a group of five genes (EIF2B) located on chromosomes 1,2,3,12, and 14 encoding subunits of translation initiation factor 2B.    

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

There is no effective treatment for the neurologic disease.  Ocular treatment for cataracts has not been reported.

References
Article Title: 

Chorioretinal dysplasia, lymphedema, and microcephaly

Clinical Characteristics
Ocular Features: 

The congenital lymphedema results in thickened and ptotic eyelids with prominent epicanthal folds.  Congenital ptosis is not uncommon in the general population in the absence of lymphedema so that this feature by itself is insufficient to diagnose this syndrome.  Retinal folds with variable degrees of pigmentary changes are often present.  Narrowed retinal vessels, atrophic nerve heads and progressive chorioretinopathy have been reported.  Visual acuity is often reduced, sometimes severely, and nystagmus may be present.

Systemic Features: 

Coarse hair follicles over the dorsum of the hands and feet and white nails when combined with the thickened, ptotic eyelids suggest the presence of lymphedema.  The hair pattern is often altered on the arms, nape of the neck, and the back.  White lines in the palms are also suggestive.  The 'facial phenotype' includes full cheeks, flat nasal bridge and underdeveloped supraorbital ridges, up slanting palpebral fissures, broad nose with rounded tip, anteverted nares, and a long philtrum, thin upper lip, and sometimes micrognathia. The ears may appear large.  Children with this syndrome are often hypotonic during the newborn period but this feature is less evident later in childhood and improves more rapidly than the resolution of the lymphedema. The lymphedema usually improves during early childhood and is often confined to the dorsum of the hands and feet at that time.  Psychomotor development is variably delayed and some but not all patients are mentally retarded. Microcephaly is a consistent feature.

Not all features are present in all patients and, specifically, there are often microcephalic relatives who lack other signs.

Genetics

This is an autosomal dominant disorder which may consist of more than one entity but at least some cases result from heterozygous mutations in KIF11 (10q23.33).  The gene encodes a member of the kinesin family of proteins responsible for cytoplasmic mechanisms that are essential for spindle assembly and function as well in transportation of other intracellular organelles.  Mutations in this gene have also been implicated in familial exudative vitreoretinopathy (FEVR) and there is phenotypic overlap with the condition described here.

It is not unusual for microcephalic individuals to also have chorioretinal dysplasia and/or pigmentary retinopathy.  See microcephaly, chorioretinal dysplasia, mental retardation (156590), for a somewhat similar autosomal dominant condition, as well as microcephaly with chorioretinopathy, AR (251270) for an autosomal recessive condition with this combination.  Neither of these conditions is associated with congenital lymphedema, however.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

No treatment is known.

References
Article Title: 

Phenotypic Overlap Between Familial Exudative Vitreoretinopathy and Microcephaly, Lymphedema, and Chorioretinal Dysplasia Caused by KIF11 Mutations

Robitaille JM, Gillett RM, LeBlanc MA, Gaston D, Nightingale M, Mackley MP, Parkash S, Hathaway J, Thomas A, Ells A, Traboulsi EI, Heon E, Roy M, Shalev S, Fernandez CV, MacGillivray C, Wallace K, Fahiminiya S, Majewski J, McMaster CR, Bedard K. Phenotypic Overlap Between Familial Exudative Vitreoretinopathy and Microcephaly, Lymphedema, and Chorioretinal Dysplasia Caused by KIF11 Mutations. JAMA Ophthalmol. 2014 Aug 14.

PubMed ID: 
25124931

Microcephaly with or without chorioretinopathy, lymphoedema, or mental retardation (MCLMR): review of phenotype associated with KIF11 mutations

Jones GE, Ostergaard P, Moore AT, Connell FC, Williams D, Quarrell O, Brady AF, Spier I, Hazan F, Moldovan O, Wieczorek D, Mikat B, Petit F, Coubes C, Saul RA, Brice G, Gordon K, Jeffery S, Mortimer PS, Vasudevan PC, Mansour S. Microcephaly with or without chorioretinopathy, lymphoedema, or mental retardation (MCLMR): review of phenotype associated with KIF11 mutations. Eur J Hum Genet. 2013 Nov 27.  [Epub ahead of print).

PubMed ID: 
24281367

Mutations in KIF11 Cause Autosomal-Dominant Microcephaly Variably Associated with Congenital Lymphedema and Chorioretinopathy

Ostergaard P, Simpson MA, Mendola A, Vasudevan P, Connell FC, van Impel A, Moore AT, Loeys BL, Ghalamkarpour A, Onoufriadis A, Martinez-Corral I, Devery S, Leroy JG, van Laer L, Singer A, Bialer MG, McEntagart M, Quarrell O, Brice G, Trembath RC, Schulte-Merker S, Makinen T, Vikkula M, Mortimer PS, Mansour S, Jeffery S. Mutations in KIF11 Cause Autosomal-Dominant Microcephaly Variably Associated with Congenital Lymphedema and Chorioretinopathy. Am J Hum Genet. 2012 Jan 24. [Epub ahead of print].

PubMed ID: 
22284827

Chorioretinopathy with Microcephaly 1

Clinical Characteristics
Ocular Features: 

The ocular features have not been well described.  Small corneas, hyperopia, pale optic nerves and a variety of pigmentary changes in the retina have been reported.  The latter may consist of diffuse, fine or granular pigmentary changes.  Areas of pigmentary atrophy are often associated with patchy areas of pigmentary clumping.  These changes are usually located posterior to the equator.  Choroidal vessels may be sparse where the RPE is absent.  It has been suggested that the patchy pattern of retinal pigmentation resembles ocular toxoplasmosis.  Strabismus is common.  One report suggests microphthalmos in a patient.  Vision has been reported as subnormal from the first year of life but no quantitative data are available.

Systemic Features: 

Microcephaly is a consistent feature.  The forehead is steeply sloped but facial size appears normal.  The palate is highly arched.  Patients often have hyperactive deep tendon reflexes and walk with a shuffling gait.  Children are often hyperactive and highly social.  Intelligence quotients are usually subnormal. No lymphedema has been reported.  At least some patients have cutis marmorata.

On MRI diffuse pachygryria is seen.  The vermis is hypoplastic and the surface area of the corpus callosum is reduced to half of normal. 

Genetics

 Parental consanguinity was present in two reported families and pedigrees are consistent with autosomal recessive inheritance with homozygous mutations of TUBGCP6 (22p22) responsible.

This presumed recessive disorder appears to be different than the autosomal dominant disorder of lymphedema, microcephaly, and chorioretinal dysplasia  (MCLMR(152950) although molecular confirmation is lacking.

For somewhat similar disorder see Chorioretinopathy with Microcephaly 2 (616171).

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

Treatment is supportive.

References
Article Title: 

Genetic mapping and exome sequencing identify variants associated with five novel diseases

Puffenberger EG, Jinks RN, Sougnez C, Cibulskis K, Willert RA, Achilly NP, Cassidy RP, Fiorentini CJ, Heiken KF, Lawrence JJ, Mahoney MH, Miller CJ, Nair DT, Politi KA, Worcester KN, Setton RA, Dipiazza R, Sherman EA, Eastman JT, Francklyn C, Robey-Bond S, Rider NL, Gabriel S, Morton DH, Strauss KA. Genetic mapping and exome sequencing identify variants associated with five novel diseases. PLoS One. 2012;7(1):e28936. Epub 2012 Jan 17. PubMed PMID: 22279524.

PubMed ID: 
22279524

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