WS Type Research Articles

Five novel cis-regulatory deletions of SOX10 cause Waardenburg syndrome type II

IntroductionWaardenburg syndrome (WS) is a genetic disorder characterized by hearing loss, hypopigmentation, and distinct facial features. Despite > 60% molecular diagnosis rate for WS patients, pathogenic variants within coding regions are predominant, with few non-coding copy number variations (CNVs) reported.MethodsIn this study, we performed whole genome sequencing (WGS) on 59 undiagnosed WS patients and analyzed the CNVs within the promoter and enhancer regions of the SOX10 gene.ResultsWe identified five novel pathogenic deletions ranging from 448 bp to 70 kb upstream of SOX10. Two deletions were in the enhancer region, while three were in the promoter and 5'UTR region. These CNVs manifested as WS type II in eight patients from five unrelated families, demonstrating phenotypic heterogeneity. Furthermore, analysis of CNV1 within the enhancer region suggested a potential mechanism involving Alu-mediated non-allelic homologous recombination (NAHR).ConclusionOur findings extend the mutation spectrum of the SOX10 gene and elucidate the pathogenic role of CNVs in cis-regulatory elements, particularly variations in enhancer and promoter regions, thereby enhancing clinical gene detection and interpretation of non-coding regions.

Facklamia lactis sp. nov., isolated from raw milk.

Two strains of a Gram-staining-positive species were isolated from German bulk tank milk. On the basis of their 16S rRNA sequences they were affiliated to the genus Facklamia but could not be assigned to any species with a validly published name. Facklamia miroungae ATCC BAA-466T (97.3 % 16S rRNA sequence similarity), Facklamia languida CCUG 37842T (96.9 %), and Facklamia hominis CCUG 36813T (96.6 %) are the closest relatives. In the 16S rRNA phylogeny and in the core-genome phylogeny strains WS 5301T and WS 5302 form a well-supported, separate lineage. Pairwise average nucleotide identity calculated using MUMmer (ANIm) between WS 5301T and type strains of other Facklamia species is well below the species cut-off (95 %) and ranges from 83.4 to 87.7 %. The DNA G+C content of the type strain is 36.4 mol% and the assembly size of the genome is 2.2 Mb. Cells of WS 5301T are non-motile, non-endospore-forming, oxidase-negative, catalase-negative and facultatively anaerobic cocci. The fastidious species grows at 10-40 °C and with up to 7.0 % (w/v) NaCl in BHI supplemented with 5 g l-1 yeast extract. Major polar lipids are phosphatidylglycerol, diphosphatidylglycerol and two glycolipids. Predominant fatty acids are C16 : 1ω9c and C18 : 1ω9c. On the basis of their genomic, physiological and chemotaxonomic characteristics the strains examined in this study represent the same, hitherto unknown species. We propose the name Facklamia lactis sp. nov. for which WS 5301T (=DSM 111018T=LMG 31861T) is the type strain and WS 5302 (=DSM 111019=LMG 31862) is an additional strain of this novel species.

Síndrome Waardenburg Tipo I condición inusual en población pediátrica. A propósito de un caso

Introducción: El síndrome de Waardenburg (SW) es un trastorno genético poco frecuente con una incidencia de 1 por 40000 habitantes. Es originado por mutaciones en múltiples genes; estas alteraciones genéticas ocasionan anomalías en el desarrollo de los tejidos derivados de las células de la cresta neural y producen hallazgos fenotípicos característicos como iris de color azul claro o heterocromía del iris, poliosis, sordera neurosensorial, entre otros.
 Objetivo: Describir un caso clínico poco frecuente con hallazgos clínicos típicos del síndrome de Waardenburg tipo 1.
 Material y métodos Estudio descriptivo, retrospectivo, presentación de un caso clínico.
 Resultados: Se presenta un caso clínico de un pre–escolar masculino, de 3 años de edad, con antecedentes patológicos familiares: abuelo paterno, padre y hermano paterno con probable antecedente genético de SW. Se establece la importancia del índice W en el diagnóstico y clasificación del síndrome. Los hallazgos aquí reportados muestran la variabilidad de las manifestaciones fenotípicas según la clasificación. Así contribuye a un diagnóstico precoz y oportuno para actuar en beneficio de la salud de los niños. 
 Conclusiones: El Síndrome de Waarbendurg que se presenta en este caso clínico es de tipo 1, hallazgo inusual en Pediatría, se diferencia del tipo 2 clínicamente por la distopía cantorum, que es característica de WS tipo 1, se reporta este caso con el fin de contribuir en el diagnóstico precoz y a una calidad de vida.

Generation of an iPSC line (IMAGINi022-A) from a patient carrying a SOX10 missense mutation and presenting with deafness, depigmentation and progressive neurological impairment.

Mutations of SOX10 result in a broad range of phenotypes including Waardenburg syndrome (WS types 2 and 4) that can be found in association with peripheral demyelinating neuropathy and/or central dysmyelinating leukodystrophy. Here, we generated induced pluripotent stem cells (iPSCs) from a patient carrying a de novo heterozygous missense mutation in the SOX10 gene (MIM* 602229, NM006941.3c.523C>G; p.Pro175Ala) presenting with deafness, depigmentation and progressive neurological impairment. Cells were reprogrammed by non-integrative viral transduction from blood sample, have normal karyotype, express pluripotency markers and are able to differentiate into the three germ cell layers.

A novel PAX3 mutation in a Korean patient with Waardenburg syndrome type 1 and unilateral branch retinal vein and artery occlusion: a case report

BackgroundWaardenburg syndrome (WS) is a very rare genetic disorder affecting the neural crest cells. Coexistence of branch retinal vein occlusion (BRVO) and branch retinal artery occlusion (BRAO) in the same eye is also a rare finding. Here we report a case of WS type 1 that was confirmed by a novel mutation with the finding of unilateral BRVO and BRAO.Case presentationA 36-year-old, white-haired Korean man presented with a complaint of loss of vision in the inferior visual field of his right eye and hearing loss. He had telecanthus with a medial eyebrow and a hypochromic left iris. Funduscopy showed an ischemic change at the posterior pole in the right eye with sparing of the foveal center as well as retinal hemorrhages and white patches along the superotemporal arcade. Fundus angiography revealed the presence of both BRVO and BRAO, and optical coherence tomography showed thickening and opacification of the retinal layers corresponding to the ischemic area. A blood workup revealed hyperhomocysteinemia and the presence of antiphospholipid antibodies; both are suggestive as the cause of the BRVO and BRAO. Single nucleotide polymorphism analysis confirmed a novel PAX3 mutation at 2q35 (c.91–95 ACTCC deletion causing a frameshift). These findings confirmed a diagnosis of WS type 1.ConclusionsWS is a heterogeneous inherited disorder of the neural crest cells that causes pigment abnormalities and sensorineural hearing loss. This is the first report of unilateral BRVO and BRAO in a patient with WS. Furthermore, the PAX3 mutation identified in this patient has not been reported previously.

Molecular etiology and genotype-phenotype correlation of Chinese Han deaf patients with type I and type II Waardenburg Syndrome

Waardenburg syndrome (WS) characterized by sensorineural hearing loss and pigmentary abnormalities is genetically heterogeneous and phenotypically variable. This study investigated the molecular etiology and genotype-phenotype correlation of WS in 36 Chinese Han deaf probands and 16 additional family members that were clinically diagnosed with WS type I (WS1, n = 8) and type II (WS2, n = 42). Mutation screening of six WS-associated genes detected PAX3 mutations in 6 (86%) of the 7 WS1 probands. Among the 29 WS2 probands, 13 (45%) and 10 (34%) were identified with SOX10 and MITF mutations, respectively. Nineteen of the 26 detected mutations were novel. In WS2 probands whose parental DNA samples were available, de novo mutations were frequently seen for SOX10 mutations (7/8) but not for MITF mutations (0/5, P = 0.005). Excessive freckle, a common feature of WS2 in Chinese Hans, was frequent in WS2 probands with MITF mutations (7/10) but not in those with SOX10 mutations (0/13, P = 4.9 × 10−4). Our results showed that mutations in SOX10 and MITF are two major causes for deafness associated with WS2. These two subtypes of WS2 can be distinguished by the high de novo rate of the SOX10 mutations and the excessive freckle phenotype exclusively associated with the MITF mutations.

Identification of four novel mutations of the WFS1 gene in Iranian Wolfram syndrome pedigrees.

Wolfram syndrome is a rare neurodegenerative disorder with an autosomal recessive pattern of inheritance characterized by various clinical manifestations. The related gene, WFS1, encodes a transmembrane glycoprotein, named wolframin. Genetic analyses demonstrated that mutations in this gene are associated with WS type 1. Our aim in this study was to sequence WFS1 coding region in Iranian Wolfram syndrome pedigrees. Genomic DNA was extracted from peripheral blood of 12 WS patients and their healthy parents. Exons 2-8 and the exon-intron junctions of WFS1 were sequenced. DNA sequences were compared to the reference using Sequencher software. Molecular analysis of WFS1 revealed six different mutations. Four novel and two previously reported mutations were identified. One novel mutation, c.1379_1381del, is predicted to produce an aberrant protein. A second novel mutation, c.1384G>T, encodes a truncated protein. Novel mutation, c.1097-1107dup (11bp), causes a frameshift which results in a premature stop codon. We screened for the novel missense mutation, c.1010C>T, in 100 control alleles. This mutation was not found in any of the healthy controls. Our study increased the spectrum of WFS1 mutations and supported the role of WFS1 in susceptibility to WS. We hope that these findings open new horizons to future molecular investigations which may help to prevent and treat this devastating disease.

Experimental evolution reveals hidden diversity in evolutionary pathways.

Replicate populations of natural and experimental organisms often show evidence of parallel genetic evolution, but the causes are unclear. The wrinkly spreader morph of Pseudomonas fluorescens arises repeatedly during experimental evolution. The mutational causes reside exclusively within three pathways. By eliminating these, 13 new mutational pathways were discovered with the newly arising WS types having fitnesses similar to those arising from the commonly passaged routes. Our findings show that parallel genetic evolution is strongly biased by constraints and we reveal the genetic bases. From such knowledge, and in instances where new phenotypes arise via gene activation, we suggest a set of principles: evolution proceeds firstly via pathways subject to negative regulation, then via promoter mutations and gene fusions, and finally via activation by intragenic gain-of-function mutations. These principles inform evolutionary forecasting and have relevance to interpreting the diverse array of mutations associated with clinically identical instances of disease in humans.

Understanding disease mutations from the crystal structure of SOX9 with DNA

SRY(Sex determining Region Y)-box or SOX transcription factors are important in early development and maintenance of different cell pools after birth. Of the ~20 SOX proteins (SRY, SOX1-SOX15, SOX17, SOX18, SOX21 and SOX30), SOX2, SOX9 and SOX10 mutations are primarily disease-associated: SOX2 with Combined Pituitary Hormone Deficiency, Microphthalmia, Septo-optic dysplasia and anophthalmic syndrome; SOX9 with Campomelic Dysplasia (affects development of the reproductive and skeletal system); and SOX10 (~94% sequence identity to SOX9) with Waardenburg Syndrome (affects audition and pigmentation in hair, eyes and skin; and specifically with WS types 2 and 4). As part of our Protein Structure Initiative (PSI)-Biology partnership, we performed structural and mutational analyses including x-ray crystallography and surface plasmon resonance assays, on the DNA-binding HMG domain of SOX9 with duplex DNA. Crystals were obtained in C222 space group and the structure was determined by molecular replacement to 2.77 Å resolution with final Rcryst/Rfree of 24.8/27.8%. The overall structure of the SOX9-DNA complex is similar to other SOX/SRY protein complexes. The SOX9-DNA protein-DNA interactions suggested a panel of mutations to assay for biochemical activity, which allowed us to understand the molecular basis of five mutations identified in Campomelic Dysplasia. These mutated residues have direct contact with DNA as well as indirect contacts, i.e., these mutations lead to allosteric secondary structure changes in the protein, which affect residues in direct contact with DNA. Due to the very high sequence identity between SOX9 and SOX10, our crystal structure also helps to rationalize the effect of SOX10 mutations in Waardenburg Syndrome. This work is supported by NIH grants U54 GM094586 and U01 GM094614. SSRL operations are funded by DOE BES, and the SSRL SMB program by DOE BER, NIH NCRR BTP and NIH NIGMS.

Sweep visually evoked potentials and visual findings in children with West syndrome

BackgroundWest syndrome (WS) is a type of early childhood epilepsy characterized by progressive neurological development deterioration that includes vision. AimTo demonstrate the clinical importance of grating visual acuity thresholds (GVA) measurement by sweep visually evoked potentials technique (sweep-VEP) as a reliable tool for evaluation of the visual cortex status in WS children. MethodsThis is a retrospective study of the best-corrected binocular GVA and ophthalmological features of WS children referred for the Laboratory of Clinical Electrophysiology of Vision of UNIFESP from 1998 to 2012 (Committee on Ethics in Research of UNIFESP n° 0349/08). The GVA deficit was calculated by subtracting binocular GVA score (logMAR units) of each patient from the median values of age norms from our own lab and classified as mild (0.1–0.39 logMAR), moderate (0.40–0.80 logMAR) or severe (>0.81 logMAR). Associated ophthalmological features were also described. ResultsData from 30 WS children (age from 6 to 108 months, median = 14.5 months, mean ± SD = 22.0 ± 22.1 months; 19 male) were analyzed. The majority presented severe GVA deficit (0.15–1.44 logMAR; mean ± SD = 0.82 ± 0.32 logMAR; median = 0.82 logMAR), poor visual behavior, high prevalence of strabismus and great variability in ocular positioning. The GVA deficit did not vary according to gender (P = .8022), WS type (P = .908), birth age (P = .2881), perinatal oxygenation (P = .7692), visual behavior (P = .8789), ocular motility (P = .1821), nystagmus (P = .2868), risk of drug-induced retinopathy (P = .4632) and participation in early visual stimulation therapy (P = .9010). ConclusionsThe sweep-VEP technique is a reliable tool to classify visual system impairment in WS children, in agreement with the poor visual behavior exhibited by them.

Cochlear implant rehabilitation outcomes in Waardenburg syndrome children

ObjectivesThe purpose of this study was to review the outcomes of children with documented Waardenburg syndrome implanted in the ENT Department of Centro Hospitalar de Coimbra, concerning postoperative speech perception and production, in comparison to the rest of non-syndromic implanted children. MethodsA retrospective chart review was performed for children congenitally deaf who had undergone cochlear implantation with multichannel implants, diagnosed as having Waardenburg syndrome, between 1992 and 2011. Postoperative performance outcomes were assessed and confronted with results obtained by children with non-syndromic congenital deafness also implanted in our department. Open-set auditory perception skills were evaluated by using European Portuguese speech discrimination tests (vowels test, monosyllabic word test, number word test and words in sentence test). Meaningful auditory integration scales (MAIS) and categories of auditory performance (CAP) were also measured. Speech production was further assessed and included results on meaningful use of speech Scale (MUSS) and speech intelligibility rating (SIR). ResultsTo date, 6 implanted children were clinically identified as having WS type I, and one met the diagnosis of type II. All WS children received multichannel cochlear implants, with a mean age at implantation of 30.6±9.7months (ranging from 19 to 42months). Postoperative outcomes in WS children were similar to other nonsyndromic children. In addition, in number word and vowels discrimination test WS group showed slightly better performances, as well as in MUSS and MAIS assessment. ConclusionsOur study has shown that cochlear implantation should be considered a rehabilitative option for Waardenburg syndrome children with profound deafness, enabling the development and improvement of speech perception and production abilities in this group of patients, reinforcing their candidacy for this audio-oral rehabilitation method.

Complex networks: Effect of subtle changes in nature of randomness

In two different classes of network models, namely, the Watts Strogatz type and the Euclidean type, subtle changes have been introduced in the randomness. In the Watts Strogatz type network, rewiring has been done in different ways and although the qualitative results remain the same, finite differences in the exponents are observed. In the Euclidean type networks, where at least one finite phase transition occurs, two models differing in a similar way have been considered. The results show a possible shift in one of the phase transition points but no change in the values of the exponents. The WS and Euclidean type models are equivalent for extreme values of the parameters; we compare their behaviour for intermediate values.

Shape of Pods of Medicago Truncatula as a Promising Morphological Marker for Embryogenic Capacity

ABSTRACTThree different types of pods (N- normal with spines, LS- less spines and WS-without spines) were harvested from Medicago truncatula cv. R 108 1 plants grown in greenhouse. The pods with changed shape LS and WS were developed at the end of period of plant maturity at the upper part of plants. In vitro plants originated from seeds from three types of pods were obtained. Callus tissue produced from leaves and petioles of plants from type N, LS and WS showed different embryogenic potential. Callus tissue of type N formed embryos from both -leaves and petioles, while the callus from type WS was able to form embryos only from petioles. Regardless of the initial explants callus from LS plants did not show any embryogenic ability. In contrast to the regenerants from N type capable to form normal root system, those from WS type possess poor developed root system.

A splice-site mutation affecting the paired box of PAX3 in a three generation family with Waardenburg syndrome type I (WS1)

Waardenburg syndrome, an autosomal dominant disorder characterized by sensorineural hearing loss, pigmentary disturbances and other developmental defects, is the most frequent form of congenital deafness in humans. Mutations in the PAX3 gene, a transcription factor expressed during embryonic development, is associated with WS types I and III. Here we report the identification of a novel acceptor splice site mutation (86-2 A→G) in the paired domain of the human PAX3 gene causing WS type I in a three generation family.

Analysis of variability of clinical manifestations in Waardenburg syndrome

Expression of clinical findings of Waardenburg syndrome type 1 (WS1) and type 2 (WS2) is extremely variable. Using our collection of 26 WS1 and 8 WS2 families, we analyzed the occurrence, severity, and symmetry of clinical manifestations associated with WS. We found significant differences between WS1 and WS2 in deafness, and in pigmentary and craniofacial anomalies. Factor analysis was used to identify manifestations which covaried, resulting in 2 orthogonal factors. Since mean factor scores were found to differ when compared between WS1 and WS2, we suggest that these factors could be useful in distinguishing WS types. We found that the WS gene was transmitted from mothers more often than from fathers. We also extensively examined the W-Index, a continuous measure of dystopia canthorum. Our data suggest that use of the W-Index to discriminate between affected WS1 and WS2 individuals may be problematic since 1) ranges of W-Index scores of affected and unaffected individuals overlapped considerably within both WS1 and WS2, and 2) a considerable number of both affected and unaffected WS2 individuals exhibited W-index scores consistent with dystopia canthorum. Misclassification of families may have implications for risk assessment of deafness, since WS2 families have been reported to have greater incidence of deafness, as confirmed in our study.

Weak and Electromagnetic Interactions in Superconductivity Model

Starting with a Lagrangian of self-interacting lepton fields only, we construct an effective Lagrangian of the W einberg-Salam type. This shows that the photon, the Higgs boson and the weak-vector bosons are all composites of lepton and antilepton. Arbitrary parameters involved in the original WS model are largely removed. W einberg 11 and Salam 21 (WS) have proposed a unified model of weak and electromagnetic interactions through the use of the Higgs mechanism. In their model there are many elementary fields, i.e., the Riggs-scalar boson, the weak­ vector bosons, the electromagnetic field, and the leptons. We propose here a composite model of those particles except for leptons. We start with a Nambu­ J ona-Lasinio type Lagrangian 31 which describes a system of self-interacting lepton fields only, and obtain an effective Lagrangian of the WS type. This shows that the created Higgs boson, electromagnetic field, and weak-vector bosons can be considered composites of lepton and antilepton. At this point our program resembles works of Bjorken 41 and others 5> in spinor electrodynamics where they claim that a photon is a Nambu-Goldstone composite boson associated with a spontaneous breakdown of Lorentz invariance. Our pro­ gram is also analogous to the work of Eguchi and Sugawara 6> and its non-Abelian generalizationn where the authors have derived effective Lagrangians for expecta­ tion values of fermion fields which describe interactions among fermion-antifermion bound states in superconductivity models of hadrons. In these works there are certain difficulties associated with the Poincare invariance of the theory. Recently, however, we showed 8l that these difficulties can be avoided if operator equations for fermion fields are adopted, rather than the use of expectation values of fermion fields. Subsequently, Kikkawa 9 l and Kugo 101 proposed a simple derivation of the above effective Lagrangian by making use of the path-integral technique with a trick clue to Gross and Neveu.w In the present paper ~we consider how to realize the WS model in the frame­ work of superconductivity model by using the path-integral technique, and find that arbitrary parameters involved in the original WS model are largely removed. We begin with the following Lagrangian of the WS massless leptons only:

Features of the MEL × NWS recombination systems in influenza A virus: II. The formation of N-M, recombinant, strains of influenza A virus in mouse brain

The brains of infant and adult mice were inoculated with approximately equal quantities of the MEL and NWS strains of influenza A virus and recombinant N-M and WS types of virus isolated by titration at limiting infectivity in the chick embryo. The time, frequency, and consistency of isolation of N-M strains indicated that they were formed in the mouse brain and appeared about 12 hours after inoculation. WS types of virus did not appear regularly and were probably variants. N-M strains originated mostly from particles possessing shared antigenic characters of the two parent strains. The same particles gave rise at all ages to infectious NWS and to infectious MEL virus, which is not normally released when MEL alone is inoculated into adult mice. The results are most readily explained by analogy with bacterial transforming agents.