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1.
Am J Hum Genet ; 108(8): 1436-1449, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34216551

RESUMO

Despite widespread clinical genetic testing, many individuals with suspected genetic conditions lack a precise diagnosis, limiting their opportunity to take advantage of state-of-the-art treatments. In some cases, testing reveals difficult-to-evaluate structural differences, candidate variants that do not fully explain the phenotype, single pathogenic variants in recessive disorders, or no variants in genes of interest. Thus, there is a need for better tools to identify a precise genetic diagnosis in individuals when conventional testing approaches have been exhausted. We performed targeted long-read sequencing (T-LRS) using adaptive sampling on the Oxford Nanopore platform on 40 individuals, 10 of whom lacked a complete molecular diagnosis. We computationally targeted up to 151 Mbp of sequence per individual and searched for pathogenic substitutions, structural variants, and methylation differences using a single data source. We detected all genomic aberrations-including single-nucleotide variants, copy number changes, repeat expansions, and methylation differences-identified by prior clinical testing. In 8/8 individuals with complex structural rearrangements, T-LRS enabled more precise resolution of the mutation, leading to changes in clinical management in one case. In ten individuals with suspected Mendelian conditions lacking a precise genetic diagnosis, T-LRS identified pathogenic or likely pathogenic variants in six and variants of uncertain significance in two others. T-LRS accurately identifies pathogenic structural variants, resolves complex rearrangements, and identifies Mendelian variants not detected by other technologies. T-LRS represents an efficient and cost-effective strategy to evaluate high-priority genes and regions or complex clinical testing results.


Assuntos
Aberrações Cromossômicas , Análise Citogenética/métodos , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/genética , Predisposição Genética para Doença , Genoma Humano , Mutação , Variações do Número de Cópias de DNA , Feminino , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cariotipagem , Masculino , Análise de Sequência de DNA
2.
Am J Med Genet A ; 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34291880

RESUMO

Robin sequence (RS) has many genetic and nongenetic causes, including isolated Robin sequence (iRS), Stickler syndrome (SS), and other syndromes (SyndRS). The purpose of this study was to determine if the presence and type of cleft palate varies between etiologic groups. A secondary endpoint was to determine the relationship of etiologic group, cleft type, and mortality. Retrospective chart review of patients with RS at two high-volume craniofacial centers. 295 patients with RS identified. CP was identified in 97% with iRS, 95% with SS, and 70% of those with SyndRS (p < .0001). U-shaped CP was seen in 86% of iRS, 82% with SS, but only 27% with SyndRS (p < .0001). At one institution, 12 children (6%) with RS died, all from the SyndRS group (p < .0001). All died due to medical comorbidities related to their syndrome. Only 25% of children who died had a U-shaped CP. The most common palatal morphology among those who died was an intact palate. U-shaped CP was most strongly associated with iRS and SS, and with a lower risk of mortality. RS with submucous CP, cleft lip and palate or intact palate was strongly suggestive of an underlying genetic syndrome and higher risk of mortality.

3.
Laryngoscope ; 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34133757

RESUMO

OBJECTIVES/HYPOTHESIS: A tracheal cartilaginous sleeve (TCS) is a rare anomaly characterized by anterior fusion of tracheal cartilages. TCS is associated with syndromic craniosynostoses including Apert, Crouzon and Pfeiffer syndromes and FGFR2, FGFR3, and TWIST1 variants. This study presents a 30-year review of patients with syndromic craniosynostosis and TCS and describes diagnostic methods, genetic variants, surgical interventions, and long-term outcomes. STUDY DESIGN: Retrospective, single-institution review. METHODS: This review included patients with syndromic craniosynostosis and TCS treated at Seattle Children's Hospital from 1990 to 2020. Tracheostomy, genetic variants, and additional surgery were primary measures. Fisher's exact test compared need for tracheostomy in patients with proposed high-risk (FGFR2 p.W290 or FGFR2 p.C342) versus low-risk genetic variants. RESULTS: Thirty patients with TCS were identified. Average age at diagnosis was 12 months (range 2-weeks to 7.9-years; standard deviation 19.8 months). Syndromes included Pfeiffer (37%), Apert (37%), and Crouzon (26%). Severe obstructive sleep apnea was present in 76% of patients. Tracheostomy was performed in 17 patients (57%); five were successfully decannulated. Additional interventions included adenotonsillectomy (57%), nasal (20%), laryngeal (17%), and craniofacial skeletal surgery (87%). All patients with Pfeiffer syndrome and FGFR2 p.W290C variants and 83% of patients with FGFR2 p.C342 variants required tracheostomy, differing from other variants (P = .02, odds ratio 33, 95% confidence interval 1.56-697.96). One patient (3%) died. CONCLUSION: TCS contributes to multilevel airway obstruction in patients with syndromic craniosynostosis. Genetic testing in patients with FGFR2-related syndromic craniosynostoses may identify those at risk of TCS and facilitate early intervention. A better understanding of this patient population may foster individualized airway management strategies and improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 2021.

4.
5.
Am J Med Genet A ; 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33433062

RESUMO

The 41st Annual David W. Smith Workshop on Malformation and Morphogenesis was scheduled to take place in Skamania, Washington, on September 11-16, 2020. Due to the COVID-19 pandemic and the associated recommendations to avoid travel and congregation in large groups, this meeting took place differently from its original plan. Rather than bringing trainees, clinicians and researchers with an interest in congenital malformations and their underlying morphogenesis together for several days in a workshop with submitted presentations and research lectures, this meeting took place virtually. A 1 day online meeting was organized in order to allow trainees to present their work. This Conference Report includes the highest scoring abstracts submitted by trainees and presented at the 2020 virtual David W. Smith Workshop.

6.
Am J Psychiatry ; 178(1): 77-86, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384013

RESUMO

OBJECTIVE: Certain copy number variants (CNVs) greatly increase the risk of autism. The authors conducted a genetics-first study to investigate whether heterogeneity in the clinical presentation of autism is underpinned by specific genotype-phenotype relationships. METHODS: This international study included 547 individuals (mean age, 12.3 years [SD=4.2], 54% male) who were ascertained on the basis of having a genetic diagnosis of a rare CNV associated with high risk of autism (82 16p11.2 deletion carriers, 50 16p11.2 duplication carriers, 370 22q11.2 deletion carriers, and 45 22q11.2 duplication carriers), as well as 2,027 individuals (mean age, 9.1 years [SD=4.9], 86% male) with autism of heterogeneous etiology. Assessments included the Autism Diagnostic Interview-Revised and IQ testing. RESULTS: The four genetic variant groups differed in autism symptom severity, autism subdomain profile, and IQ profile. However, substantial variability was observed in phenotypic outcome in individual genetic variant groups (74%-97% of the variance, depending on the trait), whereas variability between groups was low (1%-21%, depending on the trait). CNV carriers who met autism criteria were compared with individuals with heterogeneous autism, and a range of profile differences were identified. When clinical cutoff scores were applied, 54% of individuals with one of the four CNVs who did not meet full autism diagnostic criteria had elevated levels of autistic traits. CONCLUSIONS: Many CNV carriers do not meet full diagnostic criteria for autism but nevertheless meet clinical cutoffs for autistic traits. Although profile differences between variants were observed, there is considerable variability in clinical symptoms in the same variant.


Assuntos
Transtorno Autístico/genética , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença/genética , Transtorno Autístico/diagnóstico , Transtorno Autístico/epidemiologia , Criança , Deleção de Genes , Estudos de Associação Genética , Heterozigoto , Humanos , Entrevista Psicológica , Masculino , Prevalência , Fatores de Risco , Índice de Gravidade de Doença
7.
Pediatr Res ; 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469179

RESUMO

The COVID-19 pandemic will leave an indelible mark on the careers of current medical trainees. Given the disruptions to medical education, economic impact on institutions, and the uncertainties around future job prospects, trainees are facing unprecedented challenges. This situation is especially concerning for futures of pediatric physician-scientist trainees, where concerns regarding maintaining the pipeline were well documented prior to the emergence of COVID-19. In this Perspectives article, we leverage the unique expertise of our workgroup to address concerns of physician-scientist trainees and to provide suggestions on how to navigate career trajectories in the post-COVID-19 era. We identified and addressed four major areas of concern: lack of in-person conferences and the associated decrease access to mentors and networking activities, decreased academic productivity, diminished job prospects, and mental health challenges. We also suggest actions for trainees, mentors and educational leaders, and institutions to help support trainees during the pandemic, with a goal of maintaining the pediatric physician-scientist pipeline.

8.
Am J Med Genet A ; 182(7): 1576-1591, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32500973

RESUMO

More than 50 individuals with activating variants in the receptor tyrosine kinase PDGFRB have been reported, separated based on clinical features into solitary myofibromas, infantile myofibromatosis, Penttinen syndrome with premature aging and osteopenia, Kosaki overgrowth syndrome, and fusiform aneurysms. Despite their descriptions as distinct clinical entities, review of previous reports demonstrates substantial phenotypic overlap. We present a case series of 12 patients with activating variants in PDGFRB and review of the literature. We describe five patients with PDGFRB activating variants whose clinical features overlap multiple diagnostic entities. Seven additional patients from a large family had variable expressivity and late-onset disease, including adult onset features and two individuals with sudden death. Three patients were treated with imatinib and had robust and rapid response, including the first two reported infants with multicentric myofibromas treated with imatinib monotherapy and one with a recurrent p.Val665Ala (Penttinen) variant. Along with previously reported individuals, our cohort suggests infants and young children had few abnormal features, while older individuals had multiple additional features, several of which appeared to worsen with advancing age. Our analysis supports a diagnostic entity of a spectrum disorders due to activating variants in PDGFRB. Differences in reported phenotypes can be dramatic and correlate with advancing age, genotype, and to mosaicism in some individuals.


Assuntos
Mesilato de Imatinib/uso terapêutico , Leucoencefalopatias/etiologia , Miofibromatose/congênito , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Adolescente , Adulto , Aneurisma/genética , Criança , Feminino , Estudos de Associação Genética , Humanos , Lactente , Leucoencefalopatias/tratamento farmacológico , Leucoencefalopatias/genética , Masculino , Miofibromatose/tratamento farmacológico , Miofibromatose/etiologia , Miofibromatose/genética , Linhagem , Inibidores de Proteínas Quinases/uso terapêutico
10.
Am J Med Genet A ; 182(3): 437-440, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31833187

RESUMO

Catel-Manzke syndrome is characterized by hand anomalies, Robin sequence, cardiac defects, joint hyperextensibility, and characteristic facial features. Approximately 40 patients with Catel-Manzke have been reported, all with the pathognomonic bilateral or unilateral hyperphalangy caused by an accessory bone between the second metacarpal and proximal phalanx known as Manzke dysostosis. Here we present the first case of molecularly confirmed Catel-Manzke syndrome with Robin sequence but without Manzke dysostosis.


Assuntos
Deformidades Congênitas da Mão/genética , Hidroliases/genética , Disostose Mandibulofacial/genética , Síndrome de Pierre Robin/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Deformidades Congênitas da Mão/diagnóstico , Deformidades Congênitas da Mão/patologia , Humanos , Disostose Mandibulofacial/diagnóstico , Disostose Mandibulofacial/patologia , Mutação/genética , Síndrome de Pierre Robin/diagnóstico , Síndrome de Pierre Robin/patologia
11.
Nat Med ; 25(7): 1116-1122, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31263281

RESUMO

The treatment of lymphatic anomaly, a rare devastating disease spectrum of mostly unknown etiologies, depends on the patient manifestations1. Identifying the causal genes will allow for developing affordable therapies in keeping with precision medicine implementation2. Here we identified a recurrent gain-of-function ARAF mutation (c.640T>C:p.S214P) in a 12-year-old boy with advanced anomalous lymphatic disease unresponsive to conventional sirolimus therapy and in another, unrelated, adult patient. The mutation led to loss of a conserved phosphorylation site. Cells transduced with ARAF-S214P showed elevated ERK1/2 activity, enhanced lymphangiogenic capacity, and disassembly of actin skeleton and VE-cadherin junctions, which were rescued using the MEK inhibitor trametinib. The functional relevance of the mutation was also validated by recreating a lymphatic phenotype in a zebrafish model, with rescue of the anomalous phenotype using a MEK inhibitor. Subsequent therapy of the lead proband with a MEK inhibitor led to dramatic clinical improvement, with remodeling of the patient's lymphatic system with resolution of the lymphatic edema, marked improvement in his pulmonary function tests, cessation of supplemental oxygen requirements and near normalization of daily activities. Our results provide a representative demonstration of how knowledge of genetic classification and mechanistic understanding guides biologically based medical treatments, which in our instance was life-saving.


Assuntos
Anormalidades Linfáticas/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Mutação , Proteínas Proto-Oncogênicas A-raf/genética , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Adulto , Animais , Criança , Feminino , Células HEK293 , Humanos , Anormalidades Linfáticas/tratamento farmacológico , Masculino , Sequenciamento Completo do Exoma , Peixe-Zebra
12.
Genet Med ; 21(2): 471-476, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29915381

RESUMO

PURPOSE: Among children with FGFR2-associated Pfeiffer syndrome, those with the W290C pathogenic variant (PV) are reported to have the worst clinical outcomes. Mortality is high, and severe neurocognitive impairment has been reported in all surviving patients. However, it is unclear whether these poor outcomes are an unavoidable consequence of the PV itself, or could be improved with a genotype-specific treatment approach. The purpose of this report is to describe the more intensive surgical approach used for each of the three patients with W290C PV in FGFR2 at our center, all of whom survived and have normal neurocognitive functioning. METHODS: Retrospective chart review. RESULTS: In contrast to other patients with Pfeiffer syndrome at our center, all three patients who were subsequently found to have a W290C PV required a similar and more aggressive approach based on early cephalocranial disproportion. In contrast to previously reported W290C cases, each of our three patients survived and demonstrate normal neurocognitive functioning. CONCLUSION: While previously reported outcomes in W290C-associated Pfeiffer syndrome have been extremely poor, we present three patients who underwent an intensive surgical approach and have normal development. This suggests that a personalized and aggressive surgical approach for children with W290C PV may dramatically improve clinical outcome.


Assuntos
Acrocefalossindactilia/genética , Acrocefalossindactilia/cirurgia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Procedimentos Cirúrgicos Operatórios/métodos , Acrocefalossindactilia/mortalidade , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Mutação , Estudos Retrospectivos , Resultado do Tratamento
13.
Cleft Palate Craniofac J ; 56(3): 419-424, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29750572

RESUMO

BACKGROUND: Facial asymmetry is a common referral indication for craniofacial teams but has a wide range of causes. Prompt identification of etiology is critical to treatment, as medical and surgical interventions vary depending on the cause of asymmetry in each patient. SOLUTION: A standardized diagnostic algorithm. WHAT WE DID THAT IS NEW: We developed an algorithm to assist in the diagnostic evaluation of facial asymmetry with a focus on next steps for medically actionable causes.


Assuntos
Algoritmos , Assimetria Facial , Criança , Humanos
14.
Am J Med Genet A ; 176(8): 1711-1722, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30055033

RESUMO

Multifocal atrial tachycardia (MAT) has a well-known association with Costello syndrome, but is rarely described with related RAS/MAPK pathway disorders (RASopathies). We report 11 patients with RASopathies (Costello, Noonan, and Noonan syndrome with multiple lentigines [formerly LEOPARD syndrome]) and nonreentrant atrial tachycardias (MAT and ectopic atrial tachycardia) demonstrating overlap in cardiac arrhythmia phenotype. Similar overlap is seen in RASopathies with respect to skeletal, musculoskeletal and cutaneous abnormalities, dysmorphic facial features, and neurodevelopmental deficits. Nonreentrant atrial tachycardias may cause cardiac compromise if sinus rhythm is not restored expeditiously. Typical first-line supraventricular tachycardia anti-arrhythmics (propranolol and digoxin) were generally not effective in restoring or maintaining sinus rhythm in this cohort, while flecainide or amiodarone alone or in concert with propranolol were effective anti-arrhythmic agents for acute and chronic use. Atrial tachycardia resolved in all patients. However, a 4-month-old boy from the cohort was found asystolic (with concurrent cellulitis) and a second patient underwent cardiac transplant for heart failure complicated by recalcitrant atrial arrhythmia. While propranolol alone frequently failed to convert or maintain sinus rhythm, fleccainide or amiodarone, occasionally in combination with propranolol, was effective for RASopathy patient treatment for nonreentrant atrial arrhythmia. Our analysis shows that RASopathy patients may have nonreentrant atrial tachycardia with and without associated cardiac hypertrophy. While nonreentrant arrhythmia has been traditionally associated with Costello syndrome, this work provides an expanded view of RASopathy cardiac arrhythmia phenotype as we demonstrate mutant proteins throughout this signaling pathway can also give rise to ectopic and/or MAT.


Assuntos
Cardiomiopatia Hipertrófica/genética , Síndrome de Costello/genética , Síndrome de Noonan/genética , Taquicardia Atrial Ectópica/genética , Proteínas ras/genética , Amiodarona/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/genética , Arritmias Cardíacas/fisiopatologia , Cálcio/metabolismo , Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/fisiopatologia , Síndrome de Costello/tratamento farmacológico , Síndrome de Costello/fisiopatologia , Digoxina/uso terapêutico , Feminino , Humanos , Lactente , Recém-Nascido , Síndrome LEOPARD/genética , Síndrome LEOPARD/fisiopatologia , Masculino , Síndrome de Noonan/tratamento farmacológico , Síndrome de Noonan/fisiopatologia , Propranolol/uso terapêutico , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína SOS1/genética , Taquicardia Atrial Ectópica/tratamento farmacológico , Taquicardia Atrial Ectópica/fisiopatologia , Proteínas ras/classificação
15.
Hum Mol Genet ; 27(18): 3233-3245, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29905864

RESUMO

Central conducting lymphatic anomaly (CCLA) is one of the complex lymphatic anomalies characterized by dilated lymphatic channels, lymphatic channel dysmotility and distal obstruction affecting lymphatic drainage. We performed whole exome sequencing (WES) of DNA from a four-generation pedigree and examined the consequences of the variant by transfection of mammalian cells and morpholino and rescue studies in zebrafish. WES revealed a heterozygous mutation in EPHB4 (RefSeq NM_004444.4; c.2334 + 1G>C) and RNA-Seq demonstrated that the EPHB4 mutation destroys the normal donor site, which leads to the use of a cryptic splice donor that results in retention of the intervening 12-bp intron sequence. Transient co-expression of the wild-type and mutant EPHB4 proteins showed reduced phosphorylation of tyrosine, consistent with a loss-of-function effect. Zebrafish ephb4a morpholino resulted in vessel misbranching and deformities in the lymphatic vessel development, indicative of possible differentiation defects in lymphatic vessels, mimicking the lymphatic presentations of the patients. Immunoblot analysis using zebrafish lysates demonstrated over-activation of mTORC1 as a consequence of reduced EPHB4 signaling. Strikingly, drugs that inhibit mTOR signaling or RAS-MAPK signaling effectively rescued the misbranching phenotype in a comparable manner. Moreover, knock-in of EPHB4 mutation in HEK293T cells also induced mTORC1 activity. Our data demonstrate the pathogenicity of the identified EPHB4 mutation as a novel cause of CCLA and suggesting that ERK inhibitors may have therapeutic benefits in such patients with complex lymphatic anomalies.


Assuntos
Anormalidades Linfáticas/genética , Vasos Linfáticos/metabolismo , Receptor EphB4/genética , Sequenciamento Completo do Exoma , Animais , Modelos Animais de Doenças , Células HEK293 , Heterozigoto , Humanos , Anormalidades Linfáticas/metabolismo , Anormalidades Linfáticas/patologia , Vasos Linfáticos/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Linhagem , Fosforilação , Receptores Proteína Tirosina Quinases/genética , Transdução de Sinais , Peixe-Zebra/genética
17.
Mol Autism ; 8: 58, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29090080

RESUMO

BACKGROUND: Previous studies have reported no clear critical region for medical comorbidities in children with deletions or duplications of 22q11.2. The purpose of this study was to evaluate whether individuals with small nested deletions or duplications of the LCR-A to B region of 22q11.2 show an elevated rate of autism spectrum disorder (ASD) compared to individuals with deletions or duplications that do not include this region. METHODS: We recruited 46 patients with nested deletions (n = 33) or duplications (n = 13) of 22q11.2, including LCR-A to B (ndel = 11), LCR-A to C (ndel = 4), LCR-B to D (ndel = 14; ndup = 8), LCR-C to D (ndel = 4; ndup = 2), and smaller nested regions (n = 3). Parent questionnaire, record review, and, for a subset, in-person evaluation were used for ASD diagnostic classification. Rates of ASD in individuals with involvement of LCR-B to LCR-D were compared with Fisher's exact test to LCR-A to LCR-B for deletions, and to a previously published sample of LCR-A to LCR-D for duplications. The rates of medical comorbidities and psychiatric diagnoses were determined from questionnaires and chart review. We also report group mean differences on psychiatric questionnaires. RESULTS: Individuals with deletions involving LCR-A to B showed a 39-44% rate of ASD compared to 0% in individuals whose deletions did not involve LCR-A to B. We observed similar rates of medical comorbidities in individuals with involvement of LCR-A to B and LCR-B to D for both duplications and deletions, consistent with prior studies. CONCLUSIONS: Children with nested deletions of 22q11.2 may be at greater risk for autism spectrum disorder if the region includes LCR-A to LCR-B. Replication is needed.


Assuntos
Transtorno do Espectro Autista/genética , Cromossomos Humanos Par 22 , Atividades Cotidianas , Adolescente , Adulto , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/diagnóstico , Catecol O-Metiltransferase/genética , Criança , Pré-Escolar , Deleção Cromossômica , Estudos de Coortes , Feminino , Duplicação Gênica , Humanos , Lactente , Recém-Nascido , Masculino , Proteínas Nucleares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Psicometria , Risco , Transtorno de Comunicação Social/complicações , Transtorno de Comunicação Social/diagnóstico , Adulto Jovem
18.
Am J Med Genet A ; 173(8): 2108-2125, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28548707

RESUMO

SMC1A encodes one of the proteins of the cohesin complex. SMC1A variants are known to cause a phenotype resembling Cornelia de Lange syndrome (CdLS). Exome sequencing has allowed recognizing SMC1A variants in individuals with encephalopathy with epilepsy who do not resemble CdLS. We performed an international, interdisciplinary study on 51 individuals with SMC1A variants for physical and behavioral characteristics, and compare results to those in 67 individuals with NIPBL variants. For the Netherlands all known individuals with SMC1A variants were studied, both with and without CdLS phenotype. Individuals with SMC1A variants can resemble CdLS, but manifestations are less marked compared to individuals with NIPBL variants: growth is less disturbed, facial signs are less marked (except for periocular signs and thin upper vermillion), there are no major limb anomalies, and they have a higher level of cognitive and adaptive functioning. Self-injurious behavior is more frequent and more severe in the NIPBL group. In the Dutch group 5 of 13 individuals (all females) had a phenotype that shows a remarkable resemblance to Rett syndrome: epileptic encephalopathy, severe or profound intellectual disability, stereotypic movements, and (in some) regression. Their missense, nonsense, and frameshift mutations are evenly spread over the gene. We conclude that SMC1A variants can result in a phenotype resembling CdLS and a phenotype resembling Rett syndrome. Resemblances between the SMC1A group and the NIPBL group suggest that a disturbed cohesin function contributes to the phenotype, but differences between these groups may also be explained by other underlying mechanisms such as moonlighting of the cohesin genes.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Síndrome de Cornélia de Lange/genética , Proteínas/genética , Síndrome de Rett/genética , Adolescente , Adulto , Criança , Pré-Escolar , Síndrome de Cornélia de Lange/diagnóstico , Síndrome de Cornélia de Lange/fisiopatologia , Exoma/genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Síndrome de Rett/diagnóstico , Síndrome de Rett/fisiopatologia , Espasmos Infantis/diagnóstico , Espasmos Infantis/genética , Espasmos Infantis/fisiopatologia , Adulto Jovem
19.
Am J Med Genet A ; 173(8): 2101-2107, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28504353

RESUMO

Autism spectrum disorder (ASD) is a genetically heterogeneous group of disorders characterized by impairments in social communication and restricted interests. Though some patients with ASD have an identifiable genetic cause, the cause of most ASD remains elusive. Many ASD susceptibility loci have been identified through clinical studies. We report two patients with syndromic ASD and persistent gastrointestinal issues who carry de novo deletions involving the CMIP gene detected by genome-wide SNP microarray and fluorescence in situ hybridization (FISH) analysis. Patient 1 has a 517 kb deletion within 16q23.2q23.3 including the entire CMIP gene. Patient 2 has a 1.59 Mb deletion within 16q23.2q23.3 that includes partial deletion of CMIP in addition to 12 other genes, none of which have a known connection to ASD or other clinical phenotypes. The deletion of CMIP is rare in general population and was not found among a reference cohort of approximately 12,000 patients studied in our laboratory who underwent SNP array analysis for various indications. A 280 kb de novo deletion containing the first 3 exons of CMIP was reported in one patient who also demonstrated ASD and developmental delay. CMIP has previously been identified as a susceptibility locus for specific language impairment (SLI). It is notable that both patients in this study had significant gastrointestinal issues requiring enteral feedings, which is unusual for patients with ASD, in addition to unusually elevated birth length, further supporting a shared causative gene. These findings suggest that CMIP haploinsufficiency is the likely cause of syndromic ASD in our patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Transtorno do Espectro Autista/genética , Gastroenteropatias/genética , Haploinsuficiência/genética , Adolescente , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/fisiopatologia , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/fisiopatologia , Éxons , Gastroenteropatias/complicações , Gastroenteropatias/fisiopatologia , Humanos , Hibridização in Situ Fluorescente , Masculino , Fenótipo , Deleção de Sequência/genética
20.
Am J Med Genet A ; 173(2): 414-420, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28102598

RESUMO

Relatively few patients with Cornelia de Lange syndrome (CdLS) due to SMC1A mutation have been reported, limiting understanding of the full extent of the phenotype. Compared to children with classic NIPBL-associated CdLS, patients with SMC1A-associated CdLS have a milder physical phenotype with prominent intellectual disability, high rate of cleft palate and absence of limb reductions. We present a patient with SMC1A-associated CdLS who had typical features including developmental delay, seizure disorder, feeding difficulties, hirsutism, and cleft palate. She also was found to have three novel features: (i) left ventricular non-compaction (LVNC) cardiomyopathy; (ii) microform cleft lip; and (iii) severe hyperopia and astigmatism. These features have implications regarding potential insight into the pathogenesis of the disorder, screening, and medical management. Hypertrophic cardiomyopathy has previously been reported in SMC1A-associated CdLS, but to our knowledge this is the first reported child with LVNC. Previous reports have included children with isolated clefts of the palate without involvement of the lip. When cleft palate alone is associated with a disorder, the underlying pathophysiology for clefting is sometimes secondary due to mechanical blocking of the fusion of the palatal shelves with the developing tongue. The presence of microform cleft lip in this patient suggests that the pathophysiology of clefting in SMC1A is primary rather than secondary. Few studies report ophthalmologic findings specific to SMC1A. Based on these findings, LVNC cardiomyopathy and cleft lip should be considered features of SMC1A-associated CdLS. All patients should receive echocardiogram and undergo thorough ophthalmologic evaluation as part of routine CdLS care. © 2016 Wiley Periodicals, Inc.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Fenda Labial/genética , Síndrome de Cornélia de Lange/diagnóstico , Síndrome de Cornélia de Lange/genética , Cardiopatias Congênitas/genética , Fenótipo , Transtornos da Visão/genética , Fenda Labial/diagnóstico , Ecocardiografia , Facies , Feminino , Estudos de Associação Genética , Cardiopatias Congênitas/diagnóstico , Humanos , Lactente , Transtornos da Visão/diagnóstico
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