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1.
Hum Genet ; 136(4): 377-386, 2017 04.
Article in English | MEDLINE | ID: mdl-28251352

ABSTRACT

Impairment of ubiquitin-proteasome system activity involving ubiquitin ligase genes UBE3A, UBE3B, and HUWE1 and deubiquitinating enzyme genes USP7 and USP9X has been reported in patients with neurodevelopmental delays. To date, only a handful of single-nucleotide variants (SNVs) and copy-number variants (CNVs) involving TRIP12, encoding a member of the HECT domain E3 ubiquitin ligases family on chromosome 2q36.3 have been reported. Using chromosomal microarray analysis and whole-exome sequencing (WES), we have identified, respectively, five deletion CNVs and four inactivating SNVs (two frameshifts, one missense, and one splicing) in TRIP12. Seven of these variants were found to be de novo; parental studies could not be completed in two families. Quantitative PCR analyses of the splicing mutation showed a dramatically decreased level of TRIP12 mRNA in the proband compared to the family controls, indicating a loss-of-function mechanism. The shared clinical features include intellectual disability with or without autistic spectrum disorders, speech delay, and facial dysmorphism. Our findings demonstrate that E3 ubiquitin ligase TRIP12 plays an important role in nervous system development and function. The nine presented pathogenic variants further document that TRIP12 haploinsufficiency causes a childhood-onset neurodevelopmental disorder. Finally, our data enable expansion of the phenotypic spectrum of ubiquitin-proteasome dependent disorders.


Subject(s)
Autism Spectrum Disorder/genetics , Carrier Proteins/genetics , Facies , Haploinsufficiency , Intellectual Disability/genetics , Language Development Disorders/genetics , Ubiquitin-Protein Ligases/genetics , Adolescent , Autism Spectrum Disorder/complications , Child , Child, Preschool , Cohort Studies , DNA Copy Number Variations , Female , Humans , Infant , Intellectual Disability/complications , Language Development Disorders/complications , Male
2.
Brain ; 139(Pt 3): 765-81, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26917586

ABSTRACT

Vici syndrome is a progressive neurodevelopmental multisystem disorder due to recessive mutations in the key autophagy gene EPG5. We report genetic, clinical, neuroradiological, and neuropathological features of 50 children from 30 families, as well as the neuronal phenotype of EPG5 knock-down in Drosophila melanogaster. We identified 39 different EPG5 mutations, most of them truncating and predicted to result in reduced EPG5 protein. Most mutations were private, but three recurrent mutations (p.Met2242Cysfs*5, p.Arg417*, and p.Gln336Arg) indicated possible founder effects. Presentation was mainly neonatal, with marked hypotonia and feeding difficulties. In addition to the five principal features (callosal agenesis, cataracts, hypopigmentation, cardiomyopathy, and immune dysfunction), we identified three equally consistent features (profound developmental delay, progressive microcephaly, and failure to thrive). The manifestation of all eight of these features has a specificity of 97%, and a sensitivity of 89% for the presence of an EPG5 mutation and will allow informed decisions about genetic testing. Clinical progression was relentless and many children died in infancy. Survival analysis demonstrated a median survival time of 24 months (95% confidence interval 0-49 months), with only a 10th of patients surviving to 5 years of age. Survival outcomes were significantly better in patients with compound heterozygous mutations (P = 0.046), as well as in patients with the recurrent p.Gln336Arg mutation. Acquired microcephaly and regression of skills in long-term survivors suggests a neurodegenerative component superimposed on the principal neurodevelopmental defect. Two-thirds of patients had a severe seizure disorder, placing EPG5 within the rapidly expanding group of genes associated with early-onset epileptic encephalopathies. Consistent neuroradiological features comprised structural abnormalities, in particular callosal agenesis and pontine hypoplasia, delayed myelination and, less frequently, thalamic signal intensity changes evolving over time. Typical muscle biopsy features included fibre size variability, central/internal nuclei, abnormal glycogen storage, presence of autophagic vacuoles and secondary mitochondrial abnormalities. Nerve biopsy performed in one case revealed subtotal absence of myelinated axons. Post-mortem examinations in three patients confirmed neurodevelopmental and neurodegenerative features and multisystem involvement. Finally, downregulation of epg5 (CG14299) in Drosophila resulted in autophagic abnormalities and progressive neurodegeneration. We conclude that EPG5-related Vici syndrome defines a novel group of neurodevelopmental disorders that should be considered in patients with suggestive features in whom mitochondrial, glycogen, or lysosomal storage disorders have been excluded. Neurological progression over time indicates an intriguing link between neurodevelopment and neurodegeneration, also supported by neurodegenerative features in epg5-deficient Drosophila, and recent implication of other autophagy regulators in late-onset neurodegenerative disease.


Subject(s)
Agenesis of Corpus Callosum/diagnosis , Agenesis of Corpus Callosum/genetics , Autophagy/genetics , Cataract/diagnosis , Cataract/genetics , Neurodevelopmental Disorders/diagnosis , Neurodevelopmental Disorders/genetics , Proteins/genetics , Agenesis of Corpus Callosum/complications , Animals , Autophagy-Related Proteins , Cataract/complications , Child, Preschool , Cross-Sectional Studies , Drosophila melanogaster , Female , Hippocampus/pathology , Humans , Lysosomal Membrane Proteins , Male , Mutation/genetics , Neurodevelopmental Disorders/complications , Retrospective Studies , Vesicular Transport Proteins
3.
Mutat Res ; 752(1): 6-9, 2013.
Article in English | MEDLINE | ID: mdl-22935230

ABSTRACT

Next-generation sequencing technologies can now be used to directly measure heritable de novo DNA sequence mutations in humans. However, these techniques have not been used to examine environmental factors that induce such mutations and their associated diseases. To address this issue, a working group on environmentally induced germline mutation analysis (ENIGMA) met in October 2011 to propose the necessary foundational studies, which include sequencing of parent-offspring trios from highly exposed human populations, and controlled dose-response experiments in animals. These studies will establish background levels of variability in germline mutation rates and identify environmental agents that influence these rates and heritable disease. Guidance for the types of exposures to examine come from rodent studies that have identified agents such as cancer chemotherapeutic drugs, ionizing radiation, cigarette smoke, and air pollution as germ-cell mutagens. Research is urgently needed to establish the health consequences of parental exposures on subsequent generations.


Subject(s)
Gene-Environment Interaction , Genetic Diseases, Inborn/genetics , Genomics , Animals , Environmental Pollutants/toxicity , Germ-Line Mutation , Humans , Radiation Effects , Tobacco Products/adverse effects
4.
Neuropsychol Rehabil ; 23(5): 732-54, 2013.
Article in English | MEDLINE | ID: mdl-23782342

ABSTRACT

Research in psychiatric settings has found that staff attribute the majority of in-patient aggression to immediate environmental stressors. We sought to determine if staff working with persons with brain injury-related severe and chronic impairment make similar causal attributions. If immediate environmental stressors precipitate the majority of aggressive incidents in this client group, it is possible an increased focus on the management of factors that initiate client aggression may be helpful. The research was conducted in a low-demand treatment programme for individuals with chronic cognitive impairment due to acquired brain injury. Over a six-week period, 63 staff and a research assistant reported on 508 aggressive incidents. Staff views as to the causes of client aggression were elicited within 72 hours of observing an aggressive incident. Staff descriptions of causes were categorised using qualitative methods and analysed both qualitatively and quantitatively. Aggression towards staff was predominantly preceded by (a) actions that interrupted or redirected a client behaviour, (b) an activity demand, or (c) a physical intrusion. The majority of aggressive incidents appeared hostile/angry in nature and were not considered by staff to be pre-meditated. Common treatment approaches can be usefully augmented by a renewed focus on interventions aimed at reducing antecedents that provoke aggression. Possible approaches for achieving this are considered.


Subject(s)
Aggression/psychology , Brain Injuries/psychology , Nursing Staff/psychology , Adult , Aged , Brain Injuries/therapy , Female , Humans , Male , Middle Aged , Stress, Psychological , Young Adult
6.
Childs Nerv Syst ; 28(8): 1221-6, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22661218

ABSTRACT

INTRODUCTION: There have been 23 previously published cases of patients with syndromic craniosynostosis and human tails. In many of these, the tail was composed of prominent coccygeal and sacral vertebrae, curved in a retroverted instead of in the normal anterograde fashion. This has been termed sacrococcygeal eversion. In those cases in which genetic testing results are reported, there were fibroblast growth factor receptor 2 (FGFR2) mutations. METHODS: We present three patients with Pfeiffer syndrome and sacrococcygeal eversion. Two had genetic testing and both had FGFR2 mutations, one of them a novel mutation in patients with syndromic craniosynostosis and sacrococcygeal eversion. We also briefly review the literature on craniosynostosis and human tails. RESULTS: All but one reported patient has had either Pfeiffer, Crouzon, or Beare-Stevenson syndrome. Most patients, including ours, have had severe manifestations of their syndrome. Although the pathogenesis of sacrococcygeal eversion is unknown, a similarly posteriorly curved tail bud develops in normal human embryos during the second month of gestation. CONCLUSIONS: Perhaps increased FGFR2 activation during this embryonic period leads to abnormal differentiation or regression of the tail bud and, in turn, sacrococcygeal eversion, in certain patients with severe syndromic craniosynostosis.


Subject(s)
Abnormalities, Multiple/genetics , Acrocephalosyndactylia/genetics , Craniosynostoses/genetics , Receptor, Fibroblast Growth Factor, Type 2/genetics , Sacrococcygeal Region/abnormalities , Abnormalities, Multiple/pathology , Acrocephalosyndactylia/pathology , Craniosynostoses/pathology , Female , Humans , Infant, Newborn , Male , Mutation
8.
Clin Case Rep ; 5(6): 975-979, 2017 06.
Article in English | MEDLINE | ID: mdl-28588850

ABSTRACT

Intraperitoneal amniotic fluid leak is a known complication of fetoscopic procedures that usually resolves spontaneously with expectant management. Intraperitoneal amniotic fluid leak may persist after fetoscopic procedures due to a myometrial window as well as to persistent chorioamniotic membrane disruption, which may be amenable to surgical repair.

9.
Nat Genet ; 49(3): 457-464, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28092684

ABSTRACT

Deadenylases are best known for degrading the poly(A) tail during mRNA decay. The deadenylase family has expanded throughout evolution and, in mammals, consists of 12 Mg2+-dependent 3'-end RNases with substrate specificity that is mostly unknown. Pontocerebellar hypoplasia type 7 (PCH7) is a unique recessive syndrome characterized by neurodegeneration and ambiguous genitalia. We studied 12 human families with PCH7, uncovering biallelic, loss-of-function mutations in TOE1, which encodes an unconventional deadenylase. toe1-morphant zebrafish displayed midbrain and hindbrain degeneration, modeling PCH-like structural defects in vivo. Surprisingly, we found that TOE1 associated with small nuclear RNAs (snRNAs) incompletely processed spliceosomal. These pre-snRNAs contained 3' genome-encoded tails often followed by post-transcriptionally added adenosines. Human cells with reduced levels of TOE1 accumulated 3'-end-extended pre-snRNAs, and the immunoisolated TOE1 complex was sufficient for 3'-end maturation of snRNAs. Our findings identify the cause of a neurodegenerative syndrome linked to snRNA maturation and uncover a key factor involved in the processing of snRNA 3' ends.


Subject(s)
Cerebellar Diseases/genetics , Exonucleases/genetics , Mutation/genetics , Nuclear Proteins/genetics , RNA, Small Nuclear/genetics , Alleles , Animals , Female , Humans , Male , Mice , Neurodegenerative Diseases/genetics , RNA, Messenger/genetics , Spliceosomes/genetics , Zebrafish
10.
Nat Genet ; 45(1): 83-7, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23222957

ABSTRACT

Vici syndrome is a recessively inherited multisystem disorder characterized by callosal agenesis, cataracts, cardiomyopathy, combined immunodeficiency and hypopigmentation. To investigate the molecular basis of Vici syndrome, we carried out exome and Sanger sequence analysis in a cohort of 18 affected individuals. We identified recessive mutations in EPG5 (previously KIAA1632), indicating a causative role in Vici syndrome. EPG5 is the human homolog of the metazoan-specific autophagy gene epg-5, encoding a key autophagy regulator (ectopic P-granules autophagy protein 5) implicated in the formation of autolysosomes. Further studies showed a severe block in autophagosomal clearance in muscle and fibroblasts from individuals with mutant EPG5, resulting in the accumulation of autophagic cargo in autophagosomes. These findings position Vici syndrome as a paradigm of human multisystem disorders associated with defective autophagy and suggest a fundamental role of the autophagy pathway in the immune system and the anatomical and functional formation of organs such as the brain and heart.


Subject(s)
Agenesis of Corpus Callosum/genetics , Antigens, Neoplasm/genetics , Autophagy/genetics , Cataract/genetics , Genes, Recessive , Mutation , Autophagy-Related Proteins , Biopsy , Consanguinity , Exome , Family , Humans , Intracellular Signaling Peptides and Proteins , Lysosomal Membrane Proteins , Lysosomes/metabolism , Muscle, Skeletal/pathology , Muscle, Skeletal/ultrastructure , Proteins/metabolism , Vesicular Transport Proteins
11.
Environ Mol Mutagen ; 52(1): 58-68, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20839217

ABSTRACT

Three classes of DNA damage were assessed in human placentas collected (2000-2004) from 51 women living in the Teplice region of the Czech Republic, a mining area considered to have some of the worst environmental pollution in Europe in the 1980s. Polycyclic aromatic hydrocarbon (PAH)-DNA adducts were localized and semiquantified using immunohistochemistry (IHC) and the Automated Cellular Imaging System (ACIS). More generalized DNA damage was measured both by (32)P-postlabeling and by abasic (AB) site analysis. Placenta stained with antiserum elicited against DNA modified with 7ß,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydro-benzo[a]pyrene (BPDE) revealed PAH-DNA adduct localization in nuclei of the cytotrophoblast (CT) cells and syncytiotrophoblast (ST) knots lining the chorionic villi. The highest levels of DNA damage, 49-312 PAH-DNA adducts/10(8) nucleotides, were found by IHC/ACIS in 14 immediately fixed placenta samples. An additional 37 placenta samples were stored frozen before fixation and embedding, and because PAH-DNA adducts were largely undetectable in these samples, freezing was implicated in the loss of IHC signal. The same placentas (n = 37) contained 1.7-8.6 stable/bulky DNA adducts/10(8) nucleotides and 0.6-47.2 AB sites/10(5) nucleotides. For all methods, there was no correlation among types of DNA damage and no difference in extent of DNA damage between smokers and nonsmokers. Therefore, the data show that DNA from placentas obtained in Teplice contained multiple types of DNA damage, which likely arose from various environmental exposures. In addition, PAH-DNA adducts were present at high concentrations in the CT cells and ST knots of the chorionic villi.


Subject(s)
DNA Damage , Smoking/adverse effects , Czech Republic , DNA Adducts/toxicity , DNA Damage/drug effects , Female , Humans , Immune Sera , Immunohistochemistry , In Vitro Techniques , Keratinocytes/drug effects , Keratinocytes/metabolism , Polycyclic Aromatic Hydrocarbons/toxicity , Pregnancy
12.
Eur J Hum Genet ; 19(5): 547-54, 2011 May.
Article in English | MEDLINE | ID: mdl-21248749

ABSTRACT

Non-allelic homologous recombination (NAHR) between segmental duplications in proximal chromosome 15q breakpoint (BP) regions can lead to microdeletions and microduplications. Several individuals with deletions flanked by BP3 and BP4 on 15q13, immediately distal to, and not including the Prader-Willi/Angelman syndrome (PW/AS) critical region and proximal to the BP4-BP5 15q13.3 microdeletion syndrome region, have been reported; however, because the deletion has also been found in normal relatives, the significance of these alterations is unclear. We have identified six individuals with deletions limited to the BP3-BP4 interval and an additional four individuals with deletions of the BP3-BP5 interval from 34 046 samples submitted for clinical testing by microarray-based comparative genomic hybridization (aCGH). Of four individuals with BP3-BP4 deletions for whom parental testing was conducted, two were apparently de novo and two were maternally inherited. A comparison of clinical features, available for five individuals in our study (four with deletions within BP3-BP4 and one with a BP3-BP5 deletion), with those in the literature show common features of short stature and/or failure to thrive, microcephaly, hypotonia, and premature breast development in some individuals. Although the BP3-BP4 deletion does not yet demonstrate statistically significant enrichment in abnormal populations compared with control populations, the presence of common clinical features among probands and the presence of genes with roles in development and nervous system function in the deletion region suggest that this deletion may have a role in abnormal phenotypes in some individuals.


Subject(s)
Abnormalities, Multiple/genetics , Chromosome Deletion , Chromosomes, Human, Pair 15 , Failure to Thrive/genetics , Child , Child, Preschool , Female , Humans , In Situ Hybridization, Fluorescence , Male
13.
Neuropsychol Rehabil ; 17(2): 206-29, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17454694

ABSTRACT

A forensic peer group programme adapted for bullying behaviour and antisocial attitudes in three young men with traumatic brain injury (TBI) is presented. Three TBI clients who had previously been resistant to an intensive neurobehavioural rehabilitation residential programme were enrolled into the EQUIP programme. EQUIP focused on teaching pro-social skills as they related to aggression, increasing moral development, and altering pro-aggressive attitudes. The group ran four days per week over six weeks, with each session lasting 30 minutes. Post-group assessment indicated that two of the three participants altered their beliefs regarding antisocial behaviour. At three-month follow up, of the two who demonstrated change one had returned to baseline while the other had maintained his progress. Aggression and bullying behaviour reduced in all three clients during the EQUIP programme and these improvements were maintained at three-month follow up. Self-esteem measures did not alter across the assessment period. Antisocial beliefs and their potential for change in clients with severe TBI are discussed.


Subject(s)
Aggression/psychology , Behavior Therapy , Brain Injuries/psychology , Cognition Disorders/rehabilitation , Peer Group , Adaptation, Psychological , Adult , Brain Injuries/complications , Brain Injuries/rehabilitation , Cognition Disorders/etiology , Humans , Interpersonal Relations , Male , Neuropsychological Tests , Personality Assessment , Self Concept , Social Adjustment , Treatment Outcome
14.
Pediatrics ; 119(5): e1199-202, 2007 May.
Article in English | MEDLINE | ID: mdl-17470566

ABSTRACT

We describe 5 patients who presented with musculoskeletal abnormalities in the neonatal period. All patients were initially suspected to have Larsen syndrome or Beals syndrome but were subsequently diagnosed with a TGFBR2 mutation diagnostic of Loeys-Dietz syndrome. Patients had progressive aortic enlargement, which necessitated surgical intervention for 3 patients and resulted in the death of 1 patient. Delay in diagnosis of Loeys-Dietz syndrome may be associated with adverse prognosis.


Subject(s)
Abnormalities, Multiple/diagnosis , Abnormalities, Multiple/genetics , Aortic Aneurysm, Thoracic/diagnosis , Aortic Aneurysm, Thoracic/genetics , Receptors, Transforming Growth Factor beta/genetics , Abnormalities, Multiple/surgery , Aortic Aneurysm, Thoracic/surgery , Diagnosis, Differential , Female , Humans , Infant , Infant, Newborn , Male , Mutation , Protein Serine-Threonine Kinases , Receptor, Transforming Growth Factor-beta Type II , Syndrome
15.
J Head Trauma Rehabil ; 21(2): 168-78, 2006.
Article in English | MEDLINE | ID: mdl-16569990

ABSTRACT

A 3-stage model of intervention is used to contrast the philosophy and treatment practices of 2 behavioral approaches to behavior disorder following traumatic brain injury. The first referred to here as the Operant Neurobehavioral Approach developed from neuropsychology and learning theory. The second referred to as the Relational Neurobehavioral Approach builds on the nonaversive behavioral techniques of the Operant Neurobehavioral Approach. It also incorporates principles of motivational interviewing, places more overt emphasis on the therapeutic relationship, and targets staff attributions for aggression in staff training. The strengths and weaknesses of both approaches are discussed. It is suggested that the Relational Neurobehavioral Approach is more likely to engage and/or reengage clients with traumatic brain injury who are resistant to behavior change. Research implications are discussed including the need to measure the fidelity of all intervention variables.


Subject(s)
Behavior Therapy/methods , Brain Injuries/rehabilitation , Aggression , Brain Injuries/psychology , Health Personnel/education , Humans , Internal-External Control , Motivation , Professional-Patient Relations , Reinforcement, Psychology
16.
Am J Hum Genet ; 76(4): 609-22, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15739154

ABSTRACT

Mutations in the GLI3 zinc-finger transcription factor gene cause Greig cephalopolysyndactyly syndrome (GCPS) and Pallister-Hall syndrome (PHS), which are variable but distinct clinical entities. We hypothesized that GLI3 mutations that predict a truncated functional repressor protein cause PHS and that functional haploinsufficiency of GLI3 causes GCPS. To test these hypotheses, we screened patients with PHS and GCPS for GLI3 mutations. The patient group consisted of 135 individuals: 89 patients with GCPS and 46 patients with PHS. We detected 47 pathological mutations (among 60 probands); when these were combined with previously published mutations, two genotype-phenotype correlations were evident. First, GCPS was caused by many types of alterations, including translocations, large deletions, exonic deletions and duplications, small in-frame deletions, and missense, frameshift/nonsense, and splicing mutations. In contrast, PHS was caused only by frameshift/nonsense and splicing mutations. Second, among the frameshift/nonsense mutations, there was a clear genotype-phenotype correlation. Mutations in the first third of the gene (from open reading frame [ORF] nucleotides [nt] 1-1997) caused GCPS, and mutations in the second third of the gene (from ORF nt 1998-3481) caused primarily PHS. Surprisingly, there were 12 mutations in patients with GCPS in the 3' third of the gene (after ORF nt 3481), and no patients with PHS had mutations in this region. These results demonstrate a robust correlation of genotype and phenotype for GLI3 mutations and strongly support the hypothesis that these two allelic disorders have distinct modes of pathogenesis.


Subject(s)
Abnormalities, Multiple/genetics , Craniofacial Abnormalities/genetics , DNA-Binding Proteins/genetics , Mutation , Nerve Tissue Proteins/genetics , Polydactyly/genetics , Transcription Factors/genetics , Epiglottis/abnormalities , Hamartoma/genetics , Humans , Hypertelorism/genetics , Hypothalamic Diseases/genetics , Kruppel-Like Transcription Factors , Phenotype , Syndactyly/genetics , Syndrome , Zinc Finger Protein Gli3 , Zinc Fingers/genetics
17.
Brain Inj ; 18(11): 1067-81, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15545205

ABSTRACT

Over the last two decades, the importance of executive functions in successful adaptive living has been increasingly recognized. Hence, investigation of executive functioning has become a core component of neuropsychological assessment. At present, correct identification is seen as crucial to ensuring adequate treatment, compensation and support. It is argued here that, in the medico-legal arena especially, but also in clinical practice, neuropsychological assessment may rely too heavily on data derived from office-based tests of executive functioning both for the identification of deficits and also for the prediction of their real world consequences. This paper discusses the discriminant and ecological validity of such tests and implications for the future assessment of executive functioning. Additionally, the importance of reliable behavioural observations, made in more ecologically valid environments than purely the consulting room is stressed.


Subject(s)
Cognition Disorders/diagnosis , Frontal Lobe/physiopathology , Neuropsychological Tests , Activities of Daily Living , Adaptation, Psychological , Behavior , Brain Injuries/physiopathology , Brain Injuries/psychology , Cognition Disorders/physiopathology , Cognition Disorders/psychology , Emotions/physiology , Humans , Personality/physiology , Prefrontal Cortex/physiopathology , Reproducibility of Results
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