RESUMO
POGZ (Pogo transposable element derived with ZNF domain) is known to function as a regulator of gene expression. While variations in the POGZ gene have been associated with intellectual disabilities and developmental delays in humans, the exact pathophysiological mechanisms remain unclear. To shed light on this, we created two lines of conditional knockout mice for Pogz, one specific to excitatory neurons (Emx1-Pogz mice) and the other to inhibitory neurons (Gad2-Pogz mice) in the brain. Emx1-Pogz mice showed a decrease in body weight, similar to total Pogz knockout mice. Although the two lines did not display significant morphological abnormalities in the telencephalon, impaired POGZ function affected the electrophysiological properties of both excitatory and inhibitory neurons differently. These findings suggest that these mouse lines could be useful tools for clarifying the precise pathophysiological mechanisms of neurodevelopmental disorders associated with POGZ gene abnormalities.
Assuntos
Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Animais , Humanos , Camundongos , Encéfalo , Deficiência Intelectual/genética , Camundongos Knockout , Transtornos do Neurodesenvolvimento/genética , Neurônios/metabolismoRESUMO
OBJECTIVE: Congenital hypogonadotropic hypogonadism (CHH) is a rare, genetically heterogeneous reproductive disorder caused by gonadotropin-releasing hormone (GnRH) deficiency. Approximately half of CHH patients also have decreased or absent sense of smell, that is, Kallmann syndrome (KS). We describe a patient with White-Sutton syndrome (developmental delay and autism spectrum disorder) and KS due to a heterozygous de novo mutation in POGZ (c.2857C>T, p.(Gln953*)), a gene encoding pogo transposable element derived with zinc finger domain, which acts as a transcriptomic regulator of neuronal networks. DESIGN AND METHODS: We modeled the role of POGZ in CHH by generating 2 clonal human pluripotent stem cell lines with CRISPR/Cas9, carrying either the heterozygous patient mutation (H11 line) or a homozygous mutation (c.2803-2906del; p.E935Kfs*7 encoding a truncated POGZ protein; F6del line). RESULTS: During the differentiation to GnRH neurons, neural progenitors derived from F6del line displayed severe proliferation defect, delayed wound-healing capacity, downregulation of intermediate progenitor neuron genes TBR1 and TBR2, and immature neuron markers PAX6 and TUBB3 and gave rise to fewer neurons with shorter neurites and less neurite branch points compared to the WT and H11 lines (P < .005). Both lines, however, could be successfully differentiated to GnRH neurons. CONCLUSIONS: In conclusion, this is the first report on the overlap between White-Sutton syndrome and CHH. POGZ mutations do not hinder GnRH neuron formation but may cause CHH/KS by affecting the size and motility of the anterior neural progenitor pool and neurite outgrowth.
Assuntos
Transtorno do Espectro Autista , Síndrome de Kallmann , Humanos , Síndrome de Kallmann/genética , Neurônios , Hormônio Liberador de Gonadotropina , Mutação/genéticaRESUMO
Background: Jansen de Vries Syndrome (JdVS) is a rare neurodevelopmental disorder (NDD) caused by gain-of-function (GOF) truncating mutations in PPM1D exons 5 or 6. PPM1D is a serine/threonine phosphatase that plays an important role in the DNA damage response (DDR) by negatively regulating TP53 (P53). JdVS-associated mutations lead to the formation of a truncated PPM1D protein that retains catalytic activity and has a GOF effect because of reduced degradation. Somatic PPM1D exons 5 and 6 truncating mutations are well-established factors in a number of cancers, due to excessive dephosphorylation and reduced function of P53 and other substrates involved in DDR. Children with JdVS have a variety of neurodevelopmental, psychiatric, and physical problems. In addition, a small fraction has acute neuropsychiatric decompensation apparently triggered by infection or severe non-infectious environmental stress factors. Methods: To understand the molecular basis of JdVS, we developed an induced pluripotent stem cell (iPSC) model system. iPSCs heterozygous for the truncating variant (PPM1D+/tr), were made from a patient, and control lines engineered using CRISPR-Cas9 gene editing. Proteomics and phosphoprotemics analyses were carried out on iPSC-derived glutamatergic neurons and microglia from three control and three PPM1D+/tr iPSC lines. We also analyzed the effect of the TLR4 agonist, lipopolysaccharide, to understand how activation of the innate immune system in microglia could account for acute behavioral decompensation. Results: One of the major findings was the downregulation of POGZ in unstimulated microglia. Since loss-of-function variants in the POGZ gene are well-known causes of autism spectrum disorder, the decrease in PPM1D+/tr microglia suggests this plays a role in the neurodevelopmental aspects of JdVS. In addition, neurons, baseline, and LPS-stimulated microglia show marked alterations in the expression of several E3 ubiquitin ligases, most notably UBR4, and regulators of innate immunity, chromatin structure, ErbB signaling, and splicing. In addition, pathway analysis points to overlap with neurodegenerative disorders. Limitations: Owing to the cost and labor-intensive nature of iPSC research, the sample size was small. Conclusions: Our findings provide insight into the molecular basis of JdVS and can be extrapolated to understand neuropsychiatric decompensation that occurs in subgroups of patients with ASD and other NDDs.
RESUMO
BACKGROUND: White-Sutton syndrome is an autosomal dominant neurodevelopmental disorder caused by heterozygous mutation in POGZ (Pogo Transposable Element Derived with ZNF Domain). This syndrome is characterized by delayed psychomotor development apparent in infancy and abnormal facial features. To date, 80 cases have been reported in the literature; however, the phenotypic characterizations remain incomplete. CASE PRESENTATION: We herein describe a 2-year-old girl harboring a novel frameshift de novo POGZ variant: c.2746del (p.Thr916ProfsTer12). This patient presented with multisystem abnormalities affecting the digestive tract and neurological functioning, as well as congenital heart disease, which involved an atrial septal defect (18 × 23 × 22 mm) with pulmonary arterial hypertension (42 mmHg). The relationship between congenital heart disease and White-Sutton syndrome as described in both the GeneReview and OMIM databases (#616,364) remains unclear. A review of the current literature revealed 18 cases of White-Sutton syndrome with POGZ variants and congenital heart disease, and we summarize their clinical features in this study. CONCLUSIONS: Our findings based on the present case and those in the literature indicate a relationship between POGZ mutation and congenital heart disease.
Assuntos
Anormalidades Múltiplas , Cardiopatias Congênitas , Deficiência Intelectual , Feminino , Humanos , Pré-Escolar , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/genética , Deficiência Intelectual/genética , Mutação , Mutação da Fase de Leitura , Anormalidades Múltiplas/genética , FenótipoRESUMO
ADNP and POGZ are two top-ranking risk factors for autism spectrum disorder and intellectual disability, but how they are linked to these neurodevelopmental disorders is largely unknown. Both ADNP and POGZ are chromatin regulators, which could profoundly affect gene transcription and cellular function in the brain. Using post-mortem tissue from patients with autism spectrum disorder, we found diminished expression of ADNP and POGZ in the prefrontal cortex, a region highly implicated in neurodevelopmental disorders. To understand the functional role of these neurodevelopmental disorder risk factors, we used viral-based gene transfer to investigate how Adnp or Pogz deficiency in mouse prefrontal cortex affects behavioural, transcriptomic and synaptic function. Mice with prefrontal cortex deficiency of Adnp or Pogz exhibited specific impairment of cognitive task performance. RNA-sequencing revealed that Adnp or Pogz deficiency induced prominent upregulation of overlapping genes enriched in neuroinflammation, similar to the elevation of pro-inflammatory genes in humans with neurodevelopmental disorders. Concomitantly, Adnp or Pogz deficiency led to the significant increase of pro-phagocytic microglial activation in prefrontal cortex, as well as the significant decrease of glutamatergic transmission and postsynaptic protein expression. These findings have uncovered the convergent functions of two top risk factors for autism spectrum disorder and intellectual disability in prefrontal cortex, providing a mechanism linking chromatin, transcriptional and synaptic dysregulation to cognitive deficits associated with neurodevelopmental disorders.
Assuntos
Transtorno do Espectro Autista , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Proteínas de Homeodomínio , Deficiência Intelectual , Proteínas do Tecido Nervoso , Transtornos do Neurodesenvolvimento , Animais , Transtorno do Espectro Autista/genética , Proteínas de Ciclo Celular/genética , Cromatina , Proteínas de Ligação a DNA/genética , Proteínas de Homeodomínio/genética , Humanos , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Transtornos do Neurodesenvolvimento/metabolismo , Fatores de Risco , Transposases/genética , Transposases/metabolismoRESUMO
POGZ-related disorders (also known as White-Sutton syndrome) encompass a wide range of neurocognitive abnormalities and other accompanying anomalies. Disease severity varies widely among POGZ patients and studies investigating genotype-phenotype association are scarce. Therefore, our aim was to collect data on previously unreported POGZ patients and perform a large-scale phenotype-genotype comparison from published data. Overall, 117 POGZ patients' genotype and phenotype data were included in the analysis, including 12 novel patients. A severity scoring system was developed for the comparison. Mild and severe phenotypes were compared with the types and location of the variants and the predicted presence or absence of nonsense-mediated RNA decay (NMD). Missense variants were more often associated with mild phenotypes (p = 0.0421) and truncating variants predicted to escape NMD presented with more severe phenotypes (p < 0.0001). Within this group, variants in the prolin-rich region of the POGZ protein were associated with the most severe phenotypes (p = 0.0004). Our study suggests that gain-of-function or dominant negative effect through escaping NMD and the location of the variants in the prolin-rich domain of the protein may play an important role in the severity of manifestations of POGZ-associated neurodevelopmental disorders.
Assuntos
Estudos de Associação Genética , Mutação , Transtornos do Neurodesenvolvimento/patologia , Transposases/genética , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Transtornos do Neurodesenvolvimento/genética , Adulto JovemRESUMO
The heterochromatin protein HP1 plays a central role in the maintenance of genome stability but little is known about how HP1 is controlled. Here, we show that the zinc finger protein POGZ promotes the presence of HP1 at DNA double-strand breaks (DSBs) in human cells. POGZ depletion delays the resolution of DSBs and sensitizes cells to different DNA-damaging agents, including cisplatin and talazoparib. Mechanistically, POGZ promotes homology-directed DNA repair by retaining the BRCA1/BARD1 complex at DSBs in an HP1-dependent manner. In vivo CRISPR inactivation of Pogz is embryonically lethal. Pogz haploinsufficiency (Pogz+ /delta) results in developmental delay, impaired intellectual abilities, hyperactive behaviour and a compromised humoral immune response in mice, recapitulating the main clinical features of the White Sutton syndrome (WHSUS). Pogz+ /delta mice are further radiosensitive and accumulate DSBs in diverse tissues, including the spleen and brain. Altogether, our findings identify POGZ as an important player in homology-directed DNA repair both in vitro and in vivo.
Assuntos
Homólogo 5 da Proteína Cromobox , Reparo do DNA , Deficiência Intelectual , Reparo de DNA por Recombinação , Transposases , Animais , Homólogo 5 da Proteína Cromobox/genética , Homólogo 5 da Proteína Cromobox/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , DNA , Quebras de DNA de Cadeia Dupla , Humanos , Deficiência Intelectual/genética , Camundongos , Transposases/genética , Transposases/metabolismoRESUMO
BACKGROUND: White-Sutton (WHSUS) is a recently recognized syndrome caused by mutations of the POGZ gene. Approximately 70 patients have been reported to date. Intellectual disability, hypotonia, behavioral abnormalities, autism, and typical facial dysmorphisms are recognized as WHSUS features; however, still few patients receive a comprehensive psychometric, behavioral and neurological examination. In this report, we describe the pediatric, dysmorphological, neurological, psychometric and behavioral phenotype in a new WHSUS patient due to a novel heterozygous POGZ mutation, highlighting the distinctive epileptic phenotype and the cognitive pattern. CASE PRESENTATION: The patient, an 8 years-old girl, presented history of hypotonia, motor and speech delay, and distinctive facial features. The diagnosis of WHSUS followed the identification of the de novo variant p.Asp828GlyfsTer36 (c.2482dupG) in the POGZ gene. The patient showed a distinctive neurological phenotype with the occurrence of both paroxysmal not-epileptic events in the first 6 months of age and EEG abnormalities without evidence of clinical seizures after the first year of age. Psychological and behavioral testing highlighted moderate intellectual and communication deficit, mild autism spectrum and visual-motor integration deficit. CONCLUSIONS: This is the first described case of WHSUS with a co-existence of paroxysmal not-epileptic events and abnormal EEG without seizures in the same patient. Together with the available literature data, this observation suggests that paroxysmal not-epileptic events could be more frequent than expected and that this feature belongs to the WHSUS phenotypic spectrum. Autism is a known comorbidity of WHSUS but is still poorly investigated. Specific clinical testing could help detect also mild autistic phenotypes and better define autism prevalence in POGZ-related syndrome. Special attention should be given to symptoms such as stereotypies, social withdrawal, and hyperactivity that, when present, should be considered as possible signs of autism symptoms. The dissection of the neurological and behavioral phenotype is crucial for individualized therapies tailored to patient's needs.
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Transtorno Autístico/genética , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Criança , Eletroencefalografia , Feminino , Humanos , Mutação , Fenótipo , SíndromeRESUMO
One of the recently described syndromes emerging from the massive study of cohorts of undiagnosed patients with autism spectrum disorders (ASD) and syndromic intellectual disability (ID) is White-Sutton syndrome (WHSUS) (MIM #616364), caused by variants in the POGZ gene (MIM *614787), located on the long arm of chromosome 1 (1q21.3). So far, more than 50 individuals have been reported worldwide, although phenotypic features and natural history have not been exhaustively characterized yet. The phenotypic spectrum of the WHSUS is broad and includes moderate to severe ID, microcephaly, variable cerebral malformations, short stature, brachydactyly, visual abnormalities, sensorineural hearing loss, hypotonia, sleep difficulties, autistic features, self-injurious behaviour, feeding difficulties, gastroesophageal reflux, and other less frequent features. Here, we report the case of a girl with microcephaly, brain malformations, developmental delay (DD), peripheral polyneuropathy, and adducted thumb-a remarkable clinical feature in the first years of life-and heterozygous for a previously unreported, de novo splicing variant in POGZ. This report contributes to strengthen and expand the knowledge of the clinical spectrum of WHSUS, pointing out the importance of less frequent clinical signs as diagnostic handles in suspecting this condition.
Assuntos
Transtorno do Espectro Autista/genética , Deficiência Intelectual/genética , Polineuropatias/genética , Transposases/genética , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/fisiopatologia , Cromossomos Humanos Par 1/genética , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/fisiopatologia , Masculino , Polineuropatias/diagnóstico , Polineuropatias/diagnóstico por imagem , Polineuropatias/fisiopatologia , Sequenciamento do ExomaRESUMO
The purpose of this study is to reveal the effect on the clinical phenotype of variants detected at family examination of a case of combined pogo transposable element derived with zinc finger domain (POGZ) gene, tubulin folding cofactor E (TBCE) gene, and short stature homeobox (SHOX) gene variation. A Turkish non-consanguineous family consisting of five members was investigated. Whole exome sequence analysis and chromosomal microarray analysis (CMA) were performed for a 2-year-old male patient (the proband) with global developmental delay, hypotonia, dysmorphia, and hot water epilepsy. Targeted sequence and chromosomal microarray analyses were performed for each family member. A heterozygous c.3908_3911delTCTG/p.V1303fs*6 variant was detected in the POGZ gene and a heterozygous c.626 T > G(p.L209X) variant in the TBCE gene in the proband. In addition, a gain of 0.1 MB was detected in the Xp22.33(602488-733497) × 3/Yp11.32(552488-683497) × 3 region at CMA. The SHOX (312865) gene defined in Online Mendelian Inheritance in Man is located in this region. While the proband's father and brother had heterozygous variations only in the TBCE gene, neither TBCE nor POGZ mutations were detected in the mother or sister. A gain in Xp22.33(419224-883640) × 3 was detected in the mother at CMA. Except for short stature and Madelung deformity, no phenotypical findings were detected in the mother. Other family members were also phenotypically normal. The family screening confirmed that dysmorphic findings and global developmental delay in the proband resulted from the variation in the POGZ gene, while short stature was caused by the gain in the Xp22.33(602488-733497) × 3/Yp11.32(552488-683497) × 3 region. In addition, the pathogenic POGZ gene variation in our patient may be a possible cause of hot water epilepsy. Heterozygous variation in the TBCE gene was clinically insignificant. Hot water epilepsy has not previously been reported in the rare patients with POGZ gene mutation. Additionally, in contrast to the previous literature, the proband exhibited no features of autism. It should also be remembered that posterior fossa abnormalities are frequently seen in these patients. We think that this case and family review involving POGZ and SHOX gene mutations will make a useful contribution to the existing literature.
Assuntos
Epilepsia/genética , Transtornos do Crescimento/genética , Chaperonas Moleculares/genética , Mutação , Osteocondrodisplasias/genética , Proteína de Homoeobox de Baixa Estatura/genética , Transposases/genética , Estatura/genética , Pré-Escolar , Humanos , Masculino , LinhagemRESUMO
Autism spectrum disorder (ASD) is a highly prevalent neurodevelopmental disorder characterized by core symptoms of impaired social behavior and communication. Recent studies have suggested that the oxytocin system, which regulates social behavior in mammals, is potentially involved in ASD. Mouse models of ASD provide a useful system for understanding the associations between an impaired oxytocin system and social behavior deficits. However, limited studies have shown the involvement of the oxytocin system in the behavioral phenotypes in mouse models of ASD. We have previously demonstrated that a mouse model that carries the ASD patient-derived de novo mutation in the pogo transposable element derived with zinc finger domain (POGZWT/Q1038R mice), showed ASD-like social behavioral deficits. Here, we have explored whether oxytocin (OXT) administration improves impaired social behavior in POGZWT/Q1038R mice and found that intranasal oxytocin administration effectively restored the impaired social behavior in POGZWT/Q1038R mice. We also found that the expression level of the oxytocin receptor gene (OXTR) was low in POGZWT/Q1038R mice. However, we did not detect significant changes in the number of OXT-expressing neurons between the paraventricular nucleus of POGZWT/Q1038R mice and that of WT mice. A chromatin immunoprecipitation assay revealed that POGZ binds to the promoter region of OXTR and is involved in the transcriptional regulation of OXTR. In summary, our study demonstrate that the pathogenic mutation in the POGZ, a high-confidence ASD gene, impairs the oxytocin system and social behavior in mice, providing insights into the development of oxytocin-based therapeutics for ASD.
Assuntos
Transtorno do Espectro Autista/tratamento farmacológico , Ocitocina/uso terapêutico , Comportamento Social , Transposases/genética , Administração Intranasal , Animais , Transtorno do Espectro Autista/psicologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Regulação para Baixo , Humanos , Camundongos , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ocitocina/administração & dosagem , Ocitocina/farmacologia , Mutação Puntual , Regiões Promotoras Genéticas , Ligação Proteica , Receptores de Ocitocina/biossíntese , Receptores de Ocitocina/genética , Receptores de Vasopressinas/biossíntese , Receptores de Vasopressinas/genética , Transcrição Gênica , Transposases/fisiologiaRESUMO
Efficient genetic manipulation in the developing central nervous system is crucial for investigating mechanisms of neurodevelopmental disorders and the development of promising therapeutics. Common approaches including transgenic mice and in utero electroporation, although powerful in many aspects, have their own limitations. In this study, we delivered vectors based on the AAV9.PHP.eB pseudo-type to the fetal mouse brain, and achieved widespread and extensive transduction of neural cells. When AAV9.PHP.eB-coding gRNA targeting PogZ or Depdc5 was delivered to Cas9 transgenic mice, widespread gene knockout was also achieved at the whole brain level. Our studies provide a useful platform for studying brain development and devising genetic intervention for severe developmental diseases.
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Sistema Nervoso Central/embriologia , Sistema Nervoso Central/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Dependovirus/metabolismo , Feto/metabolismo , Edição de Genes , Coloração e Rotulagem , Animais , Suscetibilidade a Doenças , Feminino , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Técnicas de Transferência de Genes , Masculino , Camundongos , Convulsões/patologiaRESUMO
White-Sutton syndrome is a rare developmental disorder characterized by global developmental delay, intellectual disabilities (ID), and neurobehavioral abnormalities secondary to pathogenic pogo transposable element-derived protein with zinc finger domain (POGZ) variants. The purpose of our study was to describe the neurocognitive phenotype of an unbiased national cohort of patients with identified POGZ pathogenic variants. This study is based on a French collaboration through the AnDDI-Rares network, and includes 19 patients from 18 families with POGZ pathogenic variants. All clinical data and neuropsychological tests were collected from medical files. Among the 19 patients, 14 patients exhibited ID (six mild, five moderate and three severe). The five remaining patients had learning disabilities and shared a similar neurocognitive profile, including language difficulties, dysexecutive syndrome, attention disorders, slowness, and social difficulties. One patient evaluated for autism was found to have moderate autism spectrum disorder. This study reveals that the cognitive phenotype of patients with POGZ pathogenic variants can range from learning disabilities to severe ID. It highlights that pathogenic variations in the same genes can be reported in a large spectrum of neurocognitive profiles, and that children with learning disabilities could benefit from next generation sequencing techniques.
Assuntos
Transtorno do Espectro Autista/genética , Deficiências do Desenvolvimento/genética , Variação Genética , Deficiência Intelectual/genética , Transtornos Neurocognitivos/genética , Transposases/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , França , Predisposição Genética para Doença , Humanos , Masculino , Mutação , Testes Neuropsicológicos , Fenótipo , Adulto JovemRESUMO
A rare developmental delay (DD)/intellectual disability (ID) syndrome with craniofacial dysmorphisms and autistic features, termed White-Sutton syndrome (WHSUS, MIM#614787), has been recently described, identifying truncating mutations in the chromatin regulator POGZ (KIAA0461, MIM#614787). We describe a further WHSUS patient harboring a novel nonsense de novo POGZ variant, which afflicts a protein domain with transposase activity less frequently impacted by mutational events (DDE domain). This patient displays additional physical and behavioral features, these latter mimicking Smith-Magenis syndrome (SMS, MIM#182290). Considering sleep-wake cycle anomalies and abnormal behavior manifested by this boy, we reinforced the clinical resemblance between WHSUS and SMS, being both chromatinopathies. In addition, using the DeepGestalt technology, we identified a different facial overlap between WHSUS patients with mutations in the DDE domain (Group 1) and individuals harboring variants in other protein domains/regions (Group 2). This report further delineates the clinical and molecular repertoire of the POGZ-related phenotype, adding a novel patient with uncommon clinical and behavioral features and provides the first computer-aided facial study of WHSUS patients.
Assuntos
Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Síndrome de Smith-Magenis/genética , Transposases/genética , Pré-Escolar , Códon sem Sentido/genética , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/diagnóstico por imagem , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/fisiopatologia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/diagnóstico por imagem , Deficiências do Desenvolvimento/fisiopatologia , Exoma/genética , Feminino , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/fisiopatologia , Masculino , Mutação/genética , Fenótipo , Síndrome de Smith-Magenis/diagnóstico , Síndrome de Smith-Magenis/diagnóstico por imagem , Síndrome de Smith-Magenis/fisiopatologiaRESUMO
White-Sutton syndrome (WHSUS) is a recently-identified genetic disorder resulting from de novo heterozygous pathogenic variants in POGZ. Thus far, over 50 individuals have been reported worldwide, however phenotypic characterization and data regarding the natural history are still incomplete. Here we report the clinical features of 22 individuals with 21 unique loss of function POGZ variants. We observed a broad spectrum of intellectual disability and/or developmental delay with or without autism, and speech delay in all individuals. Other common problems included ocular abnormalities, hearing loss and gait abnormalities. A validated sleep disordered breathing questionnaire identified symptoms of obstructive sleep apnea in 4/12 (33%) individuals. A higher-than-expected proportion of cases also had gastrointestinal phenotypes, both functional and anatomical, as well as genitourinary anomalies. In line with previous publications, we observed an increased body mass index (BMI) z-score compared to the general population (mean 0.59, median 0.9; p 0.0253). Common facial features included microcephaly, broad forehead, midface hypoplasia, triangular mouth, broad nasal root and flat nasal bridge. Analysis of the Baylor Genetics clinical laboratory database revealed that POGZ variants were implicated in approximately 0.14% of cases who underwent clinical exome sequencing for neurological indications with or without involvement of other body systems. This study describes a greater allelic series and expands the phenotypic spectrum of this new syndromic form of intellectual disability and autism.
Assuntos
Transtorno Autístico/genética , Deficiência Intelectual/genética , Transtornos do Desenvolvimento da Linguagem/genética , Transposases/genética , Adolescente , Adulto , Transtorno Autístico/patologia , Criança , Pré-Escolar , Exoma/genética , Feminino , Heterozigoto , Humanos , Lactente , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/patologia , Transtornos do Desenvolvimento da Linguagem/patologia , Masculino , Microcefalia/genética , Microcefalia/patologia , Pessoa de Meia-Idade , Mutação/genética , Fenótipo , Sequenciamento do Exoma , Adulto JovemRESUMO
POGZ is a heterochromatin protein 1 α-binding protein and regulates gene expression. On the other hand, accumulating pieces of evidence indicate that the POGZ gene abnormalities are involved in various neurodevelopmental disorders. In this study, we prepared a specific antibody against POGZ, anti-POGZ, and carried out biochemical and morphological characterization with mouse brain tissues. Western blotting analyses revealed that POGZ is expressed strongly at embryonic day 13 and then gradually decreased throughout the brain development process. In immunohistochemical analyses, POGZ was found to be enriched in cerebrocortical and hippocampal neurons in the early developmental stage. The nuclear expression was also detected in Purkinje cells in cerebellum at postnatal day (P)7 and P15 but disappeared at P30. In primary cultured hippocampal neurons, while POGZ was distributed mainly in the nucleus, it was also visualized in axon and dendrites with partial localization at synapses in consistency with the results obtained in biochemical fractionation analyses. The obtained results suggest that POGZ takes part in the regulation of synaptic function as well as gene expression during brain development.
Assuntos
Encéfalo/metabolismo , Neurogênese/fisiologia , Transposases/metabolismo , Animais , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismoRESUMO
BACKGROUND: De novo likely gene-disrupting variants of POGZ cause autism spectrum disorder (ASD) and intellectual disability. However, de novo missense variants of this gene were not well explored in neuropsychiatric disorders. METHODS: The single-molecule molecular inversion probes-based targeted sequencing method was performed on the proband. Variant was validated using Sanger sequencing in both proband and parents. Immunoblot analysis was performed to examine the expression of POGZ in patient-derived peripheral blood lymphocytes. Published POGZ de novo missense variants in neuropsychiatric disorders were reviewed. RESULTS: We detected a novel de novo missense variant in POGZ (c.1534C>A, p.H512N, NM_015100.4) in an individual with ASD. Immunoblot analysis revealed a dramatic reduction in POGZ protein in patient-derived peripheral blood lymphocytes suggesting a loss-of-function mechanism of this de novo missense variant. In addition, we collected and annotated additional eight POGZ de novo missense variants identified in neuropsychiatric disorders from literatures. CONCLUSION: Our findings will be beneficial to the functional analysis of POGZ in ASD pathogenesis, and for genetic counseling and clinical diagnosis of patients with POGZ de novo missense variants.
Assuntos
Transtorno do Espectro Autista/genética , Deficiência Intelectual/genética , Mutação de Sentido Incorreto , Transposases/genética , Povo Asiático , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/fisiopatologia , Comportamento Infantil , Pré-Escolar , Feminino , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/fisiopatologia , Linfócitos , Masculino , FenótipoRESUMO
Excess de novo likely gene-disruptive and missense variants within dozens of genes have been identified in autism spectrum disorder (ASD) and other neurodevelopmental disorders. However, many rare inherited missense variants of these high-risk genes have not been thoroughly evaluated. In this study, we analyzed the rare missense variant burden of POGZ in a large cohort of ASD patients from the Autism Clinical and Genetic Resources in China (ACGC) and further dissected the functional effect of disease-associated missense variants on neuronal development. Our results showed a significant burden of rare missense variants in ASD patients compared to the control population (Pâ¯=â¯4.6â¯×â¯10-5, ORâ¯=â¯3.96), and missense variants in ASD patients showed more severe predicted functional outcomes than those in controls. Furthermore, by leveraging published large-scale sequencing data of neurodevelopmental disorders (NDDs) and sporadic case reports, we identified 8 de novo missense variants of POGZ in NDD patients. Functional analysis revealed that two inherited, but not de novo, missense variants influenced the cellular localization of POGZ and failed to rescue the defects in neurite and dendritic spine development caused by Pogz knockdown in cultured mouse primary cortical neurons. Significantly, L1CAM, an autism candidate risk gene, is differentially expressed in POGZ deficient cell lines. Reduced expression of L1cam was able to partially rescue the neurite length defects caused by Pogz knockdown. Our study showed the important roles of rare inherited missense variants of POGZ in ASD risk and neuronal development and identified the potential downstream targets of POGZ, which are important for further molecular mechanism studies.
Assuntos
Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Predisposição Genética para Doença/genética , Mutação de Sentido Incorreto , Neurônios/patologia , Transposases/genética , Espinhas Dendríticas/patologia , Regulação para Baixo/genética , Humanos , Neuritos/patologiaRESUMO
POGZ (# 614787) encodes a multidomain nuclear protein involved in transcriptional regulation and its defective function has been recently associated with a syndromic neurodevelopmental disorder, known as White-Sutton syndrome (# 616364). While originally epileptic seizures were unreported, it seems that epilepsy represents a recurrent feature in affected subjects. Few data, however, are available on electroclinical features of POGZ-related epilepsy. We report a 5-year-old girl with a de novo inactivating POGZ mutation with a complex neurological phenotype characterized by hypotonia, severe developmental delay, and paroxysmal epileptic and nonepileptic events. Comparing this patient with the previously reported nine cases exhibiting epilepsy as associated feature, we detected that epilepsy onset is mostly during infancy (1-4 years of age), with both focal and generalized seizures. EEGs reveal that epileptic abnormalities mainly are localized in the frontal regions, and seizure control might be reached with one or multiple antiepileptic drugs. Besides dysmorphic features and other comorbidities (microcephaly, intellectual disability, absent speech, sensorineural hearing loss, and autistic spectrum disorder) major brain MR features include cortical and cerebellar atrophy, delayed myelination, and brainstem hypoplasia. Although the small number of patients reported, we were able to delineate primary electroclinical epileptic phenotype related to POGZ mutations. This would be crucial for an early identification and management of the condition.
Assuntos
Epilepsia/diagnóstico , Epilepsia/genética , Mutação , Fenótipo , Transposases/genética , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Pré-Escolar , Eletroencefalografia , Fácies , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
Exome sequencing has led to the comprehension of the molecular bases of several forms of neurodevelopmental disorders, a clinically heterogeneous group of diseases characterized by intellectual disability (ID) and autism spectrum disorder (ASD). De novo mutations in POGZ has been causally linked to isolated ASD and syndromic ID, only recently. Here we report on a 15 year-old girl in whom exome sequencing allowed to identify a de novo POGZ truncating mutation as the molecular cause underlying a complex phenotype apparently not fitting any recognized syndrome. We describe the evolution of her clinical features with age, and review published clinical data of patients with POGZ mutations to systematically analyze the clinical spectrum associated with mutations. Our finding expands the clinical and molecular spectrum of POGZ mutations. Revision of the literature indicate that moderate to severe ID, microcephaly, variable CNS malformations, reduced growth, brachytelephalangy, and facial dysmorphism represent recurrent features associated with POGZ mutations.