An additional manifestation in acrocallosal syndrome: temporal lobe hypoplasia

Acrocallosal Syndrome is a rare genetic disorder which is characterized by moderate to severe mental retardation, agenesis or hypoplasia of the corpus callosum and polydactyly of fingers and toes. The spectrum of this syndrome is very variable. Prominent forehead, broad nasal bridge, short nose and mandible, hypertelorism, epicanthic folds, large anterior fontanelle and tapered fingers, omphalocele and inguinal hernia are some other common findings in this syndrome. Twenty percent of the patients have associated brain abnormalities such as cerebral atrophy, hypothalamic dysfunction, small cerebrum, micropolygyria, hypoplasia of pons, hypoplasia of cerebellar hemispheres, hypoplasia of medulla oblongata, agenesis or hypoplasia of cerebellar vermis and corpus callosum abnormalities. Here we present a 10-month-old female infant with clinical and radiological findings indicative of acrocallosal syndrome. She was noted to have craniofacial abnormalities suggestive of acrocallosal syndrome, optic atrophy and polydactyly. MRI revealed cerebral atrophy, corpus callosum agenesis, dilated lateral ventricules and unilateral right temporal lobe hypoplasia, the latter not previously reported in the spectrum of this syndrome. Based on this observation we conclude the importance of screening brain abnormalities and present temporal lobe hypoplasia as a new additional anomaly in this syndrome.     

Marden-Walker syndrome: case report, nosologic discussion and aspects of counseling

The Marden-Walker syndrome is characterized by a mask-like face with blepharophimosis, micrognathia, cleft or high-arched palate, low-set ears, congenital joint contractures, decreased muscular mass, failure to thrive and psychomotor retardation. We report a boy with a phenotype mostly resembling the condition named Marden-Walker syndrome, with many of the criteria proposed for diagnosing this particular phenotype. In addition he had hypoplastic corpus callosum, cerebellar vermis hypoplasia, enlarged cisterna magna and vertebral abnormalities. During pregnancy there were reduced fetal movements. In the present patient the fetal hypokinesia sequence, due to central nervous system malformation, is most compatible with the diagnosis of Marden-Walker syndrome. The etiology is probably heterogeneous, but the possibility of autosomal recessive inheritance should be considered in genetic counseling.     

Joubert Syndrome 2 (JBTS2) in Ashkenazi Jews Is Associated with a TMEM216 Mutation

Patients with Joubert syndrome 2 (JBTS2) suffer from a neurological disease manifested by psychomotor retardation, hypotonia, ataxia, nystagmus, and oculomotor apraxia and variably associated with dysmorphism, as well as retinal and renal involvement. Brain MRI results show cerebellar vermis hypoplasia and additional anomalies of the fourth ventricle, corpus callosum, and occipital cortex. The disease has previously been mapped to the centromeric region of chromosome 11. Using homozygosity mapping in 13 patients from eight Ashkenazi Jewish families, we identified a homozygous mutation, R12L, in the TMEM216 gene, in all affected individuals. Thirty individuals heterozygous for the mutation were detected among 2766 anonymous Ashkenazi Jews, indicating a carrier rate of 1:92. Given the small size of the TMEM216 gene relative to other JBTS genes, its sequence analysis is warranted in all JBTS patients, especially those who suffer from associated anomalies.     

A review of 35 cases of asymmetric crying facies

A review of 35 cases of asymmetric crying facies: Congenital asymmetric crying facies (ACF) is caused by congenital hypoplasia or agenesis of the depressor anguli oris muscle (DAOM) on one side of the mouth. It is well known that this anomaly is frequently associated with cardiovascular, head and neck, musculoskeletal, respiratory, gastrointestinal, central nervous system, and genitourinary anomalies. In this article we report 35 ACF patients (28 children and 7 adults) and found additional abnormalities in 16 of them (i.e. 45%). The abnormalities were cerebral and cerebellar atrophy, mega-cisterna magna, mental motor retardation, convulsions, corpus callosum dysgenesis, cranial bone defect, dermoid cyst, spina bifida occulta, hypertelorism, micrognatia, retrognatia, hemangioma on the lower lip, short frenulum, cleft palate, low-set ears, preauricular tag, mild facial hypoplasia, sternal cleft, congenital heart defect, renal hypoplasia, vesicoureteral reflux, hypertrophic osteoarthropathy, congenital joint contractures, congenital hip dislocation, polydactyly, and umbilical and inguinal hernia. Besides these, one infant was born to a diabetic mother, and had atrial septal defect and the four other children had 4p deletion, Klinefelter syndrome, isolated CD4 deficiency and Treacher-Collins like facial appearance, respectively Although many of these abnormalities were reported in association with ACF, cerebellar atrophy, sternal cleft, cranial bone defect, infant of diabetic mother, 4p deletion, Klinefelter syndrome, isolated CD4 deficiency and Treacher-Collins like facial appearance were not previously published.     

MICrocephaly,disproportionate pontine and cerebellar hypoplasia syndrome: A clinico-radiologic phenotype linked to calcium/calmodulin-dependent serine protein kinase gene mutation

MICrocephaly, disproportionate pontine and cerebellar hypoplasia (MICPCH) syndrome, a rare X-linked disorder, generally seen in girls, is characterized by neurodevelopmental delay, microcephaly, and disproportionate pontine and cerebellar hypoplasia. It is caused by inactivating calcium/calmodulin-dependent serine protein kinase (CASK) gene mutations. We report a 2-year-old girl with severe neurodevelopmental delay, microcephaly, minimal pontine hypoplasia, cerebellar hypoplasia, and normal looking corpus callosum, with whom the conventional cytogenetic studies turned out to be normal, and an array-comparative genomic hybridization (a-CGH) analysis showed CASK gene duplication at Xp11.4. Our case highlights the importance of using clinico-radiologic phenotype to guide genetic investigation and it also confirms the role of a-CGH analysis in establishing the genetic diagnosis of MICPCH syndrome, when conventional cytogenetic studies are inconclusive.     

A new case of neonatal progeroid syndrome with agenesis of corpus callosum

We report on a female infant with a history of severe intrauterine and postnatal growth retardation, pseudohydrocephaloid cranium, frontal bossing, widened fontanelles, prominent scalp veins, progeroid face, entropion, beaked nose, small mouth, generalized lipodystrophy, camptodactyly and hypoplasia of lower limb muscles, suggesting the diagnosis of neonatal progeroid syndrome (NPS). In addition, she had congenital hip dysplasia and agenesis of corpus callosum. It is the first Hungarian case with neonatal progeroid syndrome.     

Smoothened and ARL13B are critical in mouse for superior cerebellar peduncle targeting

Patients with the ciliopathy Joubert syndrome present with physical anomalies, intellectual disability, and a hindbrain malformation described as the “molar tooth sign” due to its appearance on an MRI. This radiological abnormality results from a combination of hypoplasia of the cerebellar vermis and inappropriate targeting of the white matter tracts of the superior cerebellar peduncles. ARL13B is a cilia-enriched regulatory GTPase established to regulate cell fate, cell proliferation, and axon guidance through vertebrate Hedgehog signaling. In patients, mutations in ARL13B cause Joubert syndrome. To understand the etiology of the molar tooth sign, we used mouse models to investigate the role of ARL13B during cerebellar development. We found that ARL13B regulates superior cerebellar peduncle targeting and these fiber tracts require Hedgehog signaling for proper guidance. However, in mouse, the Joubert-causing R79Q mutation in ARL13B does not disrupt Hedgehog signaling nor does it impact tract targeting. We found a small cerebellar vermis in mice lacking ARL13B function but no cerebellar vermis hypoplasia in mice expressing the Joubert-causing R79Q mutation. In addition, mice expressing a cilia-excluded variant of ARL13B that transduces Hedgehog normally showed normal tract targeting and vermis width. Taken together, our data indicate that ARL13B is critical for the control of cerebellar vermis width as well as superior cerebellar peduncle axon guidance, likely via Hedgehog signaling. Thus, our work highlights the complexity of ARL13B in molar tooth sign etiology.     

69,XXX karyotype in a malformed liveborn female. Maternal origin of triploidy

A liveborn female with a 69,XXX karyotype and clinical features of triploidy syndrome is reported. Main phenotypical features are: intrauterine growth retardation, hypotonicity, micrognathism, low-set ears, ocular anomalies, syndactyly and atrophy of the cerebral cortex and corpus callosum. Study of chromosomal heteromorphisms revealed that triploidy might have arisen through fertilization of a diploid ovum by a haploid sperm (diginy).     

Syndrome of renal, genital and feet malformations.

We report a 2 months old girl affected by renal hypoplasia, genital abnormalities, syndactyly and a pattern of minor anomalies. Although the pattern of malformations overlaps the Townwes-Brock syndrome and that reported by Green et al in 1996, differential diagnosis was made with other several syndromes including acral and renal anomalies.     

Oculo-auriculo-vertebral (Goldenhar) spectrum associated with pericentric inversion 9: coincidental findings or etiologic factor?

Oculo-auriculo-vertebral (OAV) spectrum or Goldenhar syndrome is a complex and heterogeneous condition characterized by hemifacial microsomia (unilateral ear abnormalities and ipsilateral mandibular hypoplasia) as well as vertebral anomalies and epibulbar dermoids or lipodermoids. Although most cases of OAV spectrum are sporadic, both autosomal recessive and autosomal dominant inheritance have been reported. Furthermore, the association of OAV spectrum with different types of chromosomal abnormalities has been described. We present a premature newborn delivered after 36 weeks of gestation, whose birth weight was 2,100 g, birth length 43 cm and head circumference 32.5 cm. OAV spectrum with associated axial skeleton anomalies, eventration of the right hemidiaphragm, accessory spleen, unlobulated right lung, agenesis of right kidney, right ovary and right uterine horn, and partial agenesis of corpus callosum were found. She was the second child of unrelated parents, who have a healthy boy. Both parents refused chromosomal analysis of their peripheral blood. Trypsin G-banding and C-banding chromosomal analysis of the patient's peripheral blood revealed a pericentric inversion of chromosome 9 with break points at p11 and q13. This may be a coincidental or causal finding.     

The Roberts' syndrome

Summary A report is given on a small-for-date male infant showing the following symptoms: bilateral aplasia of humerus, radius, and ulna, shortened femora, bilateral cleft lip and cleft palate, stigmata of dysmorphism, and notably; simple helix formation of the ear, simian crease, clinodactylia, bilateral clubfoot deformity, hypospadia, thrombocytopenia, micrognathia, and contractures in the knee joints.Postmortem autopsy revealed horseshoe kidney, ureterstenosis with hydronephrosis, persistent branchial arches, and absence of the knee joints.Chromosome analysis results performed by G-band technique turned out normal. This, obviously, was a case of the so-called Roberts' syndrome. Our results were compared with the relevant literature and some particularities were especially emphasized. The question was discussed as to whether the SC-phocomelia (pseudothalidomid syndrome), the TAR syndrome, and reported single cases might be an identical syndrome.     

The Meckel-Gruber syndrome gene, MKS3, is mutated in Joubert syndrome

Joubert syndrome (JS) is an autosomal recessive disorder characterized by cerebellar vermis hypoplasia associated with hypotonia, developmental delay, abnormal respiratory patterns, and abnormal eye movements. The association of retinal dystrophy and renal anomalies defines JS type B. JS is a genetically heterogeneous condition with mutations in two genes, AHI1 and CEP290, identified to date. In addition, NPHP1 deletions identical to those that cause juvenile nephronophthisis have been identified in a subset of patients with a mild form of cerebellar and brainstem anomaly. Occipital encephalocele and/or polydactyly have occasionally been reported in some patients with JS, and these phenotypic features can also be observed in Meckel-Gruber syndrome (MKS). MKS is a rare, autosomal recessive lethal condition characterized by central nervous system malformations (typically, occipital meningoencephalocele), postaxial polydactyly, multicystic kidney dysplasia, and ductal proliferation in the portal area of the liver. Since there is obvious phenotypic overlap between JS and MKS, we hypothesized that mutations in the recently identified MKS genes, MKS1 on chromosome 17q and MKS3 on 8q, may be a cause of JS. After mutation analysis of MKS1 and MKS3 in a series of patients with JS (n=22), we identified MKS3 mutations in four patients with JS, thus defining MKS3 as the sixth JS locus (JBTS6). No MKS1 mutations were identified in this series, suggesting that the allelism is restricted to MKS3.     

Neuroanatomy in fragile X females: the posterior fossa.

The relative homogeneity of the neuropsychiatric phenotype in individuals with fragile (fra) X syndrome suggests that there are consistent central nervous system (CNS) abnormalities underlying the observed cognitive and behavioral abnormalities. In this study, the neuroanatomy of the posterior fossa and other selected CNS regions in 12 young fra X females were compared with those of a group of 12 age-, sex-, and IQ-matched females without evidence of the fra X syndrome. Fra X females were shown to have decreased size of the posterior cerebellar vermis and increased size of the fourth ventricle, findings that are identical to those previously reported for fra X males. When compared with fra X male and nonfra X control groups, the distribution of the posterior-vermis and fourth-ventricle variables for the fra X female group was intermediate. These results support the hypothesis that the fra X genetic abnormality leads to hypoplasia of the posterior cerebellar vermis, a neuroanatomical variation of potential importance to both developmental and neuropsychiatric syndromes.     

Do we consider Andermann syndrome in infants with agenesis of corpus callosum

Andermann syndrome is characterized by agenesis of corpus callosum, anterior horn cell disease, a mixed sensory and motor neuropathy, and facial dysmorphism, and is inherited as an autosomal recessive trait. A 7-month-old boy was admitted with developmental retardation. Head control was not gained and he could not sit. He had high arched palate, elongated facies and large angle of the mandible, which were compatible with the Andermann syndrome. Moderate hypotonicity and absent tendon reflexes were also noted. Serum creatine kinase level was normal. Magnetic resonance imaging of the brain showed agenesis of the corpus callosum. Electromyographic examination revealed the presence of both sensory and motor neuropathy. The patient was diagnosed as having the Andermann syndrome according to the clinical and laboratory findings and he is reported due to rare presentation.     

Supernumerary chromosome der(22)t(11;22): Emanuel syndrome associates with novel features

Emanuel syndrome results from +der(22)t(11q23;22q11). Cleft palate, ear anomalies, heart defects, genital anomalies, hypotonia, and mental retardation are the main features of the syndrome. We report a nine-year-old boy with the t(11;22)(q23;q11) chromosome, transmitted in an unbalanced fashion from his mother, and originated in the maternal grandmother's meiosis. In addition to mental retardation, hypotonia, craniofacial anomalies, and cryptorchidism, he has novel findings such as, joint hyperextensibility, left liver lobe agenesis, left sided malposition of the gallbladder and pancreas hypoplasia. This is the first report associating these features with Emanuel syndrome.     

X pentasomy: A case and review

Summary A 49,XXXXX girl is reported. The most typical features of the patient are: severe mental retardation, serious dental anomalies, various anomalies of the bones, and a high rate of gonadotropins. The few similar cases so far described are reviewed to aid in delineation of this rare syndrome. The implications of Lyon's hypothesis on X-aneuploidies are also discussed.     

A family with segregation of an unbalanced translocation (7;13) (q36;q32) in three patients with severe mental retardation, microcephaly and dysmorphic features, detected by subtelomere FISH: genetic counselling and prenatal diagnosis

We report a Sardinian family in which three members showed a mental-retardation-microcephaly-multiple malformations syndrome resulting from an unbalanced translocation (7;13)(q36;q32) which led to subtelomeric trisomy 7q36qter and partial monosomy 13q32qter. The unbalanced translocation was transmitted by alternate segregation from a female and a male carriers of the balanced translocation. The three patients had severe mental retardation, microcephaly and multiple minor facial and fingers anomalies. Neuroimages showed brain atrophy, associated in two patients with partial agenesis of the corpus callosum. FISH with chromosome 13 and 7 specific painting probes and subtelomere specific probes was instrumental for defining and characterizing the chromosomal translocation. Extensive genetic counseling and prenatal diagnosis has been offered to all the members of the family.     

Linkage analysis in families with Joubert syndrome plus oculo-renal involvement identifies the CORS2 locus on chromosome 11p12-q13.3

Joubert syndrome (JS) is an autosomal recessive developmental brain condition characterized by hypoplasia/dysplasia of the cerebellar vermis and by ataxia, hypotonia, oculomotor apraxia, and neonatal breathing dysregulation. A form of JS that includes retinal dysplasia and cystic dysplastic kidneys has been differentiated from other forms of JS, called either "JS type B" or "cerebello-oculo-renal syndrome" (CORS), but the genetic basis of this condition is unknown. Here, we describe three consanguineous families that display CORS. Linkage analysis defines a novel locus on chromosome 11p12-q13.3, with a maximum two-point LOD score of Z=5.2 at the marker D11S1915. Therefore, the cerebello-oculo-renal form of JS is a distinct genetic entity from the Joubert syndrome 1 (JBTS1) locus described elsewhere, in which there is minimal involvement of retina or kidney. We suggest the term "CORS2" for this new locus.