An unusual clinical characterization of a male with distal partial trisomy 1q42.1 and monosomy 4q35.1 and review of the literature

We report a male patient with a karyotype of 46,XY, der(4)t(1;4)(q42.1;q35.1) inherited from a maternal balanced translocation involving chromosome 1q and 4q. The boy had corpus callosum dysgenesis, laryngomalacia, tracheobronchus, facial dysmorphism, simian creases, and developmental retardation. The first three features are unique compared to previous literature reports on distal partial trisomy 1q. This case report allows a further delineation of the distal partial trisomy 1q syndrome.     

GPSM2 mutations cause the brain malformations and hearing loss in Chudley-McCullough syndrome

Autosomal-recessive inheritance, severe to profound sensorineural hearing loss, and partial agenesis of the corpus callosum are hallmarks of the clinically well-established Chudley-McCullough syndrome (CMS). Although not always reported in the literature, frontal polymicrogyria and gray matter heterotopia are uniformly present, whereas cerebellar dysplasia, ventriculomegaly, and arachnoid cysts are nearly invariant. Despite these striking brain malformations, individuals with CMS generally do not present with significant neurodevelopmental abnormalities, except for hearing loss. Homozygosity mapping and whole-exome sequencing of DNA from affected individuals in eight families (including the family in the first report of CMS) revealed four molecular variations (two single-base deletions, a nonsense mutation, and a canonical splice-site mutation) in the G protein-signaling modulator 2 gene, GPSM2, that underlie CMS. Mutations in GPSM2 have been previously identified in people with profound congenital nonsyndromic hearing loss (NSHL). Subsequent brain imaging of these individuals revealed frontal polymicrogyria, abnormal corpus callosum, and gray matter heterotopia, consistent with a CMS diagnosis, but no ventriculomegaly. The gene product, GPSM2, is required for orienting the mitotic spindle during cell division in multiple tissues, suggesting that the sensorineural hearing loss and characteristic brain malformations of CMS are due to defects in asymmetric cell divisions during development.     

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.     

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.     

Small terminal 10q26 deletion in a male patient with Noonan-like stigmata: diagnosis by cytogenetic and FISH analysis

A male patient is reported with terminal 10q26 deletion, developmental retardation, special behaviour, and multiple clinical anomalies including hypotonia, short stature of postnatal onset, short webbed neck, craniofacial dysmorphism, pectus excavatum with widely spaced small nipples, cryptorchidism with scrotal hypoplasia, limb and musculoskeletal anomalies. The facial dysmorphism mainly consisted of trigonocephaly, a long, triangular and asymmetrical face, hypertelorism with pseudoepicanthus, broad nasal bridge, high-arched palate, retrognathia, low-set dysplastic auricles and, on ophthalmologic examination, strabismus, astigmatism and myopia. Some of these clinical stigmata were suggesting the diagnosis of Noonan syndrome. The extremities showed special features including shortening of proximal limbs, brachydactyly with syndactyly of toes II-III and left fingers III-IV, hypoplastic toenails and joint abnormalities. A diastasis of abdominal muscles was noted and, on X-rays a thoracic scoliosis and bilateral coxa valga were evidenced. Analyses of G- and T-banded chromosomes complemented by FISH analyses using different subtelomere probes detected a terminal 10q26 deletion. Subsequent FISH studies using different probes of the 10q26 region were performed in an attempt to closely define the breakpoint and the extent of the deletion and, thereby, to allow karyotype/phenotype comparison between this patient and a previously reported case with an apparently similar 10q26 deletion.     

Thrombocytopenia-absent radius (tar) syndrome: a case with agenesis of corpus callosum, hypoplasia of cerebellar vermis and horseshoe kidney

The thrombocytopenia-absent radius (TAR) syndrome (MIM 274000) is a congenital malformation syndrome characterised by bilateral absence of the radii with present thumbs, hypomegakaryocytic thrombocytopenia and a number of additional features including skeletal and cardiac anomalies. Mental retardation, reported in about 7% of patients, is usually secondary to intracranial hemorrhage. In 1994 there was a single report of a girl with TAR syndrome and hypoplasia of the cerebellar vermis and corpus callosum and in 2003 another case of TAR syndrome with cerebellar dysgenesis has been reported. In 2000 there was first report of horseshoe kidney in association with TAR syndrome followed by a clinical study of 34 cases with TAR syndrome in 2002 where horseshoe kidney was noted in two cases. Here we report of a girl with TAR syndrome, severe mental retardation, agenesis of corpus callosum, hypoplasia of cerebellar vermis and horseshoe kidney. There is no previous report of a child with TAR syndrome and all those associated anomalies in the same patient.     

Concomitant Fractional Anisotropy and Volumetric Abnormalities in Temporal Lobe Epilepsy: Cross-Sectional Evidence for Progressive Neurologic Injury

Background

In patients with temporal lobe epilepsy and associated hippocampal sclerosis (TLEhs) there are brain abnormalities extending beyond the presumed epileptogenic zone as revealed separately in conventional magnetic resonance imaging (MRI) and MR diffusion tensor imaging (DTI) studies. However, little is known about the relation between macroscopic atrophy (revealed by volumetric MRI) and microstructural degeneration (inferred by DTI).

Methodology/Principal Findings

For 62 patients with unilateral TLEhs and 68 healthy controls, we determined volumes and mean fractional anisotropy (FA) of ipsilateral and contralateral brain structures from T1-weighted and DTI data, respectively. We report significant volume atrophy and FA alterations of temporal lobe, subcortical and callosal regions, which were more diffuse and bilateral in patients with left TLEhs relative to right TLEhs. We observed significant relationships between volume loss and mean FA, particularly of the thalamus and putamen bilaterally. When corrected for age, duration of epilepsy was significantly correlated with FA loss of an anatomically plausible route - including ipsilateral parahippocampal gyrus and temporal lobe white matter, the thalamus bilaterally, and posterior regions of the corpus callosum that contain temporal lobe fibres - that may be suggestive of progressive brain degeneration in response to recurrent seizures.

Conclusions/Significance

Chronic TLEhs is associated with interrelated DTI-derived and volume-derived brain degenerative abnormalities that are influenced by the duration of the disorder and the side of seizure onset. This work confirms previously contradictory findings by employing multi-modal imaging techniques in parallel in a large sample of patients.     

Chromosome 17p13.3 deletion syndrome: aCGH characterization,prenatal findings and diagnosis,and literature review

We report a molecular cytogenetic characterization of 17p13.3 deletion syndrome by array comparative genomic hybridization (aCGH), fluorescence in situ hybridization (FISH) and quantitative polymerase chain reaction (qPCR) in a fetus with lissencephaly, corpus callosum dysgenesis, ventriculomegaly, microcephaly, intrauterine growth restriction (IUGR), polyhydramnios and single umbilical artery. aCGH analysis revealed a 3.17-Mb deletion at 17p13.3, or arr [hg19] 17p13.3 (0–3,165,530)×1. The qPCR assays revealed a maternal origin of the deletion. Metaphase FISH analysis detected the absence of the LIS1 probe signal on the aberrant chromosome 17. The karyotype was 46,XX,del(17)(p13.3). We review the literature of chromosome 17p13.3 deletion syndrome with prenatal findings and diagnosis, and suggest that prenatal ultrasound detection of central nervous system anomalies such as lissencephaly, corpus callosum dysgenesis/agenesis, ventriculomegaly and microcephaly associated with IUGR, polyhydramnios, congenital heart defects, abdominal wall defects and renal abnormalities should include a differential diagnosis of chromosome 17p13.3 deletion syndrome.     

Emanuel syndrome due to unusual segregation of paternal origin

Emanuel syndrome is an inherited chromosomal abnormality resulting from 3:1 meiotic segregation from parental balanced translocation carrier t(11;22)(q23;q11), mostly of maternal origin. It is characterized by mental retardation, microcephaly, preauricular tag or sinus, ear anomalies, cleft or high arched palate, micrognathia, congenital heart diseases, kidney abnormalities, structural brain anomalies and genital anomalies in male. Here in, we describe a female patient with supernumerary der(22) syndrome (Emanuel syndrome) due to balanced translocation carrier father t(11;22) (q23;q11). She was mentally and physically disabled and had most of the craniofacial dysmorphism of this syndrome. Our patient had cleft palate, maldeveloped corpus callosum and hind brain with normal internal organs. Additionally, arachnodactyly, hyperextensibility of hand joints, abnormal deep palmar and finger creases, extra finger creases and bilateral talipus were evident and not previously described with this syndrome. Cytogenetic analysis and FISH documented that the patient had both translocation chromosomes plus an additional copy of der(22) with karyotyping: 47,XX,t(11; 22)(q23;q11),+der(22)t(11;22)(q23;q11). We postulated that this rare chromosomal complement can arise from; 2:2 segregation in the first meiotic division of the balanced translocation father followed by non-disjunction at meiosis II in the balanced spermatocyte.     

Pai syndrome: first patient with agenesis of the corpus callosum and literature review

BACKGROUND: Pai syndrome (PS) is a rare regional developmental defect of the face, mainly characterized by the variable association of midline cleft of the upper lip (MCL), duplicated maxillary median frenulum, and midline facial cutaneous and midanterior alveolar process polyps. Its entire clinical spectrum is still poorly delineated and the etiology remains unknown. CASE: We describe a 1-month-old boy presenting with MCL, left nostril hamartomatous mass, midline pedunculated polyp originating from the columella base, midline alveolar cleft, duplication of the upper median frenulum, unilateral persistent papillary membrane, lipoma of the corpus callosum, and additional minor facial dysmorphism. This patient also presents with agenesis of the corpus callosum, which has never been reported in PS. Literature review was carried out comparing clinical data of the 20 previously published patients with those observed in the present case. CONCLUSIONS: The minimum diagnostic criteria for PS has been fixed in one or more hamartomatous nasal polyps plus MCL (with or without cleft alveolus) and/or midanterior alveolar process congenital polyp. Additional common ancillary findings include duplicated median maxillary frenulum, hypertelorism, nasal cleft, midfrontal skin tags, and ocular and CNS structural abnormalities. However, mental retardation is only an occasional feature and seems to be related to coexisting conditions (such as chromosome imbalance). Literature review shows that PS is etiologically heterogeneous, as it may result from chromosome abnormalities and environmental/stochastic events, as well as de novo mutations.     

Bilateral receptive fields in cortical area SII: contribution of the corpus callosum and other interhemispheric commissures

The corpus callosum contributes to the interhemispheric transfer of somatosensory information. Since the somatosensory pathways are essentially crossed, a number of studies have postulated that the corpus callosum may be responsible for the presence of bilateral receptive fields (RFs) in cortical area SII. Moreover, subcortical structures, as well as some of the other commissures, may also contribute to the bilateral nature of these cells. In order to assess the relative importance of the corpus callosum, this study compared the RF properties of cells in area SII of callosum-sectioned cats to normal cats, using single-cell recordings. Results showed that the corpus callosum makes an important contribution to the bilateral activation of cells in SII, since the proportion of cells with bilateral RFs found in callosum-sectioned cats was less than half that obtained in normal cats. The decrease in the proportion of bilateral RFs was found for all body regions with the exception of the face. However, the substantial number of bilateral RFs remaining in callosotomized cats indicates that this structure is not the sole contributor to the bilateral activation of cells in SII. In order to determine whether this residual bilateral activation might be mediated by the other interhemispheric commissures, a group of cats was subjected, besides the callosotomy, to the additional transection of their subcortical commissures, including the anterior, posterior, habenular, and intertectal commissures, as well as the massa intermedia. When this group of deep-split cats was compared to the callosotomized group, the results indicated that the contribution of the other commissures to bilateral activation is negligible, since approximately the same proportion of bilateral RFs was encountered in the two groups. The relative importance of the callosal contribution to bilateral RFs of different body regions is discussed with respect to the roles commonly attributed to this structure.     

White Matter Changes in Patients with Amnestic Mild Cognitive Impairment Detected by Diffusion Tensor Imaging

Compared to normal aging adults, individuals with amnestic mild cognitive impairment (aMCI) have significantly increased risk for progressing into Alzheimer’s disease (AD). Autopsy studies found that most of the brains of aMCI cases showed anatomical features associated with AD pathology. The recent development of non-invasive neuroimaging technique, such as diffusion tensor imaging (DTI), makes it possible to investigate the microstructures of the cerebral white matter in vivo. We hypothesized that disrupted white matter (WM) integrity existed in aMCI. So we used DTI technique, by measuring fractional anisotropy (FA) and mean diffusivity (MD), to test the brain structures involved in patients with aMCI. DTI scans were collected from 40 patients with aMCI, and 28 normal controls (NC). Tract-based spatial statistics (TBSS) analyses of whole-brain FA and MD images in each individual and group comparisons were carried out. Compared to NC, aMCI patients showed significant FA reduction bilaterally, in the association and projection fibers of frontal, parietal, and temporal lobes, corpus callosum, bilateral corona radiation, right posterior thalamic radiation and right sagittal stratum. aMCI patients also showed significantly increased MD widespreadly in the association and projection fibers of frontal, parietal and temporal lobes, and corpus callosum. Assessment of the WM integrity of the frontal, parietal, temporal lobes, and corpus callosum by using DTI measures may aid early diagnosis of aMCI.     

Double autosomal trisomy (1q21.2----qter and 14pter----q13) in a female fetus with nuchal oedema

In this report we describe the prenatal diagnosis of a double autosomal trisomy (1q21.2----qter and 14pter----q13) in a female fetus with nuchal oedema, microphthalmia of the left eye and craniofacial dysmorphism. Cytogenetic examination of the parents revealed an autosomal reciprocal 1q/14q translocation with karyotype: 46,XX,t(1;14)(q21.2;q13) in the mother.     

Cortical Grey Matter and Subcortical White Matter Brain Microstructural Changes in Schizophrenia Are Localised and Age Independent: A Case-Control Diffusion Tensor Imaging Study

It is still unknown whether the structural brain impairments that characterize schizophrenia (SZ) worsen during the lifetime. Here, we aimed to describe age-related microstructural brain changes in cortical grey matter and subcortical white matter of patients affected by SZ. In this diffusion tensor imaging study, we included 69 patients diagnosed with SZ and 69 healthy control (HC) subjects, age and gender matched. We carried out analyses of covariance, with diagnosis as fixed factor and brain diffusion-related parameters as dependent variables, and controlled for the effect of education. White matter fractional anisotropy decreased in the entire age range spanned (18–65 years) in both SZ and HC and was significantly lower in younger patients with SZ, with no interaction (age by diagnosis) effect in fiber tracts including corpus callosum, corona radiata, thalamic radiations and external capsule. Also, grey matter mean diffusivity increased in the entire age range in both SZ and HC and was significantly higher in younger patients, with no age by diagnosis interaction in the left frontal operculum cortex, left insula and left planum polare and in the right temporal pole and right intracalcarine cortex. In individuals with SZ we found that localized brain cortical and white matter subcortical microstructural impairments appear early in life but do not worsen in the 18–65 year age range.     

Multimodal Magnetic Resonance Imaging Study of Treatment-Na?ve Adults with Attention-Deficit/Hyperactivity Disorder

Background

Attention-Deficit/Hiperactivity Disorder (ADHD) is a prevalent disorder, but its neuroanatomical circuitry is still relatively understudied, especially in the adult population. The few morphometric magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) studies available to date have found heterogeneous results. This may be at least partly attributable to some well-known technical limitations of the conventional voxel-based methods usually employed to analyze such neuroimaging data. Moreover, there is a great paucity of imaging studies of adult ADHD to date that have excluded patients with history of use of stimulant medication.

Methods

A newly validated method named optimally-discriminative voxel-based analysis (ODVBA) was applied to multimodal (structural and DTI) MRI data acquired from 22 treatment-naïve ADHD adults and 19 age- and gender-matched healthy controls (HC).

Results

Regarding DTI data, we found higher fractional anisotropy in ADHD relative to HC encompassing the white matter (WM) of the bilateral superior frontal gyrus, right middle frontal left gyrus, left postcentral gyrus, bilateral cingulate gyrus, bilateral middle temporal gyrus and right superior temporal gyrus; reductions in trace (a measure of diffusivity) in ADHD relative to HC were also found in fronto-striatal-parieto-occipital circuits, including the right superior frontal gyrus and bilateral middle frontal gyrus, right precentral gyrus, left middle occipital gyrus and bilateral cingulate gyrus, as well as the left body and right splenium of the corpus callosum, right superior corona radiata, and right superior longitudinal and fronto-occipital fasciculi. Volumetric abnormalities in ADHD subjects were found only at a trend level of significance, including reduced gray matter (GM) in the right angular gyrus, and increased GM in the right supplementary motor area and superior frontal gyrus.

Conclusions

Our results suggest that adult ADHD is associated with neuroanatomical abnormalities mainly affecting the WM microstructure in fronto-parieto-temporal circuits that have been implicated in cognitive, emotional and visuomotor processes.     

Asymmetrical gonadal dysgenesis. Report of a case (author's transl)]

The authors report a case of asymmetrical gonadal dysgenesis related to 45XO-46XY mosaicism in a 16 year old girl. Delayed growth and puberty, Turner's dysmorphism without sexual ambiguity and skeletal abnormalities are the main clinical features suggesting the diagnosis. Exploratory laparotomy reveals infantil uterus, bilateral fallopian tubes and streak gonads. A right dysgenetic testis is identified on electron microscopic examination. Theories on pathogenesis of this unusual genetic defect are discussed.     

The degenerative process during development of the corpus callosum

The ontogenesis of the corpus callosum is inextricably linked with the various processes controlling prosencephalic development. Our study is based on series of frontal and sagittal sections through the prosencephalon of 16 and 17 day mouse embryos and on ultrathin sections of the septum, particularly of the zone where the callosal fibres cross. The septum, which contains the first callosal fibres, does not undergo the fusional process described by other authors. The passage of pioneer fibres from one hemisphere to the other is preceded by the degeneration and death of the atrocytes of the cortical plate in the fundus of the interhemispheric issure, and by proliferation of the subependymal cells. The proliferation and migration of the subependymal cells from the medial angles of the lateral ventricles may well assist the passage of pioneering callosal fibres.