RESUMO
Ramon syndrome (OMIM #266270) was first described in a patient with cherubism, gingival fibromatosis, epilepsy, intellectual disability, hypertrichosis, and stunted growth. In 2018, Mehawej et al. described a patient with Ramon syndrome in whom a homozygous variant in ELMO2 was identified, suggesting that this gene may be the causative for this syndrome. ELMO2 biallelic pathogenic variants were also described in patients with a primary intraosseous vascular malformation (PIVM; OMIM #606893). These patients presented gingival bleeding and cherubism phenotype. Herein, a patient with gingival hypertrophy, neurodevelopmental delay, and cherubism phenotype with a novel homozygous predicted loss-of-function (LOF) variant in the ELMO2 gene and family recurrence was reported. A surgical approach to treat gingival bleeding and mandible vascular malformation was also described. Furthermore, this study includes a comprehensive literature review of molecular data regarding the ELMO2 gene. All the variants, except one described in the ELMO2, were predicted as LOF, including our patient's variant. There is an overlapping between PIVM, also caused by LOF biallelic variants in the ELMO2 gene, and Ramon syndrome, which can suggest that they are not different entities. However, due to a limited number of cases described with molecular evaluation, it is hard to establish a genotype-phenotype correlation. Our study supports that LOF pathogenic biallelic variants in the ELMO2 gene cause a phenotype that has cherubism and gingival hypertrophy as main characteristics.
Assuntos
Alelos , Querubismo , Hipertrofia Gengival , Fenótipo , Humanos , Querubismo/genética , Querubismo/patologia , Querubismo/diagnóstico , Hipertrofia Gengival/genética , Hipertrofia Gengival/patologia , Masculino , Feminino , Fibromatose Gengival/genética , Fibromatose Gengival/patologia , Fibromatose Gengival/diagnóstico , Criança , Proteínas Adaptadoras de Transdução de Sinal/genética , Homozigoto , Mutação/genéticaRESUMO
Heterozygous variants in USP9X are associated with female-restricted X-linked mental retardation (MRXS99F), a rare syndrome characterized by neurodevelopmental delay, intellectual disability (ID), and a wide variety of additional congenital anomalies. Here, we report a girl harboring a novel de novo loss-of-function variant in USP9X (c.4091delinsAG, p.Thr1364Lysfs*7), and literature review revealed novel prenatal features associated with MRXS99F, expanding the genotypic and phenotypic landscape of the syndrome. It is important to consider X-linked diseases in girls with ID and perform directed molecular investigation to provide correct diagnosis and prognosis.
Assuntos
Deficiência Intelectual/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Transtornos do Neurodesenvolvimento/genética , Ubiquitina Tiolesterase/genética , Pré-Escolar , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Lactente , Deficiência Intelectual/patologia , Mutação com Perda de Função/genética , Deficiência Intelectual Ligada ao Cromossomo X/patologia , Transtornos do Neurodesenvolvimento/patologia , FenótipoRESUMO
PURPOSE: Somatic variants in tumor necrosis factor receptor-associated factor 7 (TRAF7) cause meningioma, while germline variants have recently been identified in seven patients with developmental delay and cardiac, facial, and digital anomalies. We aimed to define the clinical and mutational spectrum associated with TRAF7 germline variants in a large series of patients, and to determine the molecular effects of the variants through transcriptomic analysis of patient fibroblasts. METHODS: We performed exome, targeted capture, and Sanger sequencing of patients with undiagnosed developmental disorders, in multiple independent diagnostic or research centers. Phenotypic and mutational comparisons were facilitated through data exchange platforms. Whole-transcriptome sequencing was performed on RNA from patient- and control-derived fibroblasts. RESULTS: We identified heterozygous missense variants in TRAF7 as the cause of a developmental delay-malformation syndrome in 45 patients. Major features include a recognizable facial gestalt (characterized in particular by blepharophimosis), short neck, pectus carinatum, digital deviations, and patent ductus arteriosus. Almost all variants occur in the WD40 repeats and most are recurrent. Several differentially expressed genes were identified in patient fibroblasts. CONCLUSION: We provide the first large-scale analysis of the clinical and mutational spectrum associated with the TRAF7 developmental syndrome, and we shed light on its molecular etiology through transcriptome studies.
Assuntos
Deficiência Intelectual , Transcriptoma , Exoma , Células Germinativas , Humanos , Deficiência Intelectual/genética , Mutação de Sentido Incorreto , Fenótipo , Transcriptoma/genética , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose TumoralRESUMO
Germline pathogenic variants in the DNA mismatch repair genes (MMR): MLH1, MSH2, MSH6, and PMS2, are causative of Lynch syndrome (LS). However, many of the variants mapping outside the invariant splice site positions (IVS ± 1, IVS ± 2) are classified as variants of unknown significance (VUS). Three such variants (MLH1 c.588+5G>C, c.588+5G>T and c.677+5G>A) were identified in 8 unrelated LS families from Argentina, Brazil and Chile. Herein, we collected clinical information on these families and performed segregation analysis and RNA splicing studies to assess the implication of these VUS in LS etiology. Pedigrees showed a clear pattern of variant co-segregation with colorectal cancer and/or other LS-associated malignancies. Tumors presented deficient expression of MLH1-PMS2 proteins in 7/7 of the LS families, and MSI-high status in 3/3 cases. Moreover, RNA analyses revealed that c.588+5G>C and c.588+5G>T induce skipping of exon 7 whereas c.677+5G>A causes skipping of exon 8. In sum, we report that the combined clinical findings in the families and the molecular studies provided the evidences needed to demonstrate that the three MLH1 variants are causative of LS and to classify c.588+5G>C and c.677+5G>A as class 5 (pathogenic), and c.588+5G>T as class 4 (likely-pathogenic). Our findings underline the importance of performing clinical and family analyses, as well as RNA splicing assays in order to determine the clinical significance of intronic variants, and contribute to the genetic counseling and clinical management of patients and their relatives.
Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Íntrons , Proteína 1 Homóloga a MutL/genética , Sítios de Splice de RNA , Splicing de RNA , Adulto , Argentina , Brasil , Chile , Neoplasias Colorretais/genética , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Reparo de Erro de Pareamento de DNA , Éxons , Feminino , Aconselhamento Genético , Humanos , Masculino , Pessoa de Meia-Idade , Endonuclease PMS2 de Reparo de Erro de Pareamento/deficiência , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/metabolismo , Proteína 1 Homóloga a MutL/deficiência , Proteína 1 Homóloga a MutL/metabolismo , Linhagem , Isoformas de ProteínasRESUMO
Prader-Willi syndrome (PWS) is one of the common neurogenetic disorders associated with intellectual disability. PWS involves a complex inheritance pattern and is caused by an absence of gene expression on the paternally inherited 15q11.2-q13 region, either due to deletion, maternal uniparental disomy or imprinting defect. The syndrome is characterized principally by severe neonatal hypotonia, a weak suck in infancy that is later followed by hyperphagia and obesity, developmental delay, intellectual disability and short stature. In the case of the chromosome 15q26-qter deletion syndrome or Drayer's syndrome, very few reports have been published. Its characteristics include intrauterine growth restriction, postnatal growth failure, varying degrees of intellectual disability, developmental delay, typical facial appearance and diaphragmatic hernia. The present paper describes a female patient in whom clinical findings were suggestive of PWS and deletion in the 15q26-qter region. Both karyotyping and methylation-specific polymerase chain reaction were shown to be normal. Nevertheless, fluorescence in situ hybridization showed a 15qter deletion that was later mapped by single nucleotide polymorphism (SNP)-array. The deleted genomic region involves the insulin-like growth factor-1 receptor (IGF1R) gene, which is related to short stature, developmental delay and intellectual disability. This case had various clinical characteristics in common with the cases of 15q26-qter deletionand characteristics compatible with PWS.
Assuntos
Anormalidades Múltiplas/genética , Transtornos do Crescimento/genética , Deficiência Intelectual/genética , Microcefalia/genética , Síndrome de Prader-Willi/genética , Anormalidades Múltiplas/patologia , Feminino , Transtornos do Crescimento/patologia , Humanos , Deficiência Intelectual/patologia , Microcefalia/patologia , Fenótipo , Síndrome de Prader-Willi/patologia , Receptor IGF Tipo 1/genética , Adulto JovemRESUMO
Objective: To evaluate the difference between chromosomal abnormalities between the gender of couples affected by Recurrent miscarriage (RM) and if there is an association between previous obstetric history and chromosomal abnormalities of the parents.Methods: Multicenter, retrospective, observational study from seven different RM clinics between 2006 and 2016. We enrolled 707 couples (1014 participants) with a history of RM. We compared the frequency of chromosomal abnormalities between groups of couples with primary and secondary RM and separated between women and their partners. Furthermore, we compared the prevalence of chromosomal abnormalities between groups based on the number of previous spontaneous abortions.Results: The overall prevalence of all cytogenetic abnormalities was 5.59% (n = 1414, women and their partners). Excluding cases of polymorphism and inversion of chromosome 9, which are considered variants of normality, the prevalence in all individuals was 2.26% (n = 32/1414). The comparative analysis of cases of chromosomal abnormalities among couples with primary and secondary RM based on the number of previous miscarriages (PM) revealed a similar frequency between groups. The statistical analysis of the total cases (primary PM + secondary PM) in these three groups were as follows: (a) couple, 2 pm versus 3 pm vs. ≥4 PM, p = .514; (b) women, 2 pm versus 3 pm vs. ≥4 PM, p = .347; and (3) partner, 2 pm versus 3 pm vs. ≥4 PM, p = .959. Chromosomal abnormalities were significantly more prevalent among women than among their partners (6.9 versus 4.2%; p = .027). Moreover, the distribution of leading chromosomal abnormalities among women was different compared with their partners. Among women, we observed these abnormalities in the following frequency order: mosaicism (38.8%), polymorphism (32.6%), translocation (16.3%), and inversion (12.3%). Among their partners, these abnormalities were polymorphism (73.3%), inversion (13.3%), mosaicism (6.7%), and translocation (6.7%).Conclusion: The number of PM and the history of full-term pregnancy does not correlate with an increase or decrease in the prevalence of cytogenetic abnormalities in couples with RM.
Assuntos
Aborto Habitual/genética , Aberrações Cromossômicas/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores SexuaisRESUMO
Atelosteogenesis type I (AOI) is an autosomal dominant skeletal dysplasia caused by mutations in the filaminB (FLNB) gene with classic and well-recognizable clinical findings. However, parents affected with a mild phenotype, probably with somatic mosaicism, can generate offspring with a much more severe phenotype of AOI. In the present report, we describe a female newborn with classic AOI leading to early neonatal death, whose diagnostic was based on prenatal radiological findings and on the physical examination of the father. Since her father had limb deformities and corporal asymmetry, suggesting somatic mosaicism, his biological samples were analyzed through a gene panel for skeletal dysplasias. A missense mutation not previously described in the literature was detected in the FLNB gene, affecting â¼ 20% of the evaluated cells and, therefore, confirming the diagnosis of mosaic AOI in the father. The molecular analysis of the father was crucial to suggest the diagnosis of AOI in the newborn, since she died early and there were no biological samples available.
A atelosteogênese tipo I (AOI) é uma displasia esquelética autossômica dominante causada por mutações no gene filamina B (FLNB) com achados clínicos clássicos e bem reconhecíveis. No entanto, pais afetados com um fenótipo mais leve, provavelmente com mosaicismo somático, podem gerar uma prole com um fenótipo muito mais grave de AOI. No presente relato, descrevemos um recém-nascido do sexo feminino com AOI clássica, que levou à morte neonatal precoce, e cujo diagnóstico foi baseado em achados radiológicos pré-natais e no exame físico de seu genitor. Como o genitor apresentava deformidades em membros e assimetria corporal, que sugeriam mosaicismo somático, suas amostras biológicas foram analisadas por meio de um painel de genes para displasias esqueléticas. Uma mutação missense, não descrita anteriormente na literatura, foi detectada no gene FLNB, afetando â¼ 20% das células avaliadas, e, portanto, confirmando o diagnóstico de AOI em mosaico no genitor. A análise molecular realizada no genitor foi fundamental para sugerir o diagnóstico de AOI na recém-nascida, uma vez que esta morreu precocemente, e não havia amostras biológicas disponíveis.
Assuntos
Mosaicismo , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/genética , Herança Paterna/genética , Fenótipo , Ultrassonografia Pré-Natal , Adolescente , Feminino , Humanos , Masculino , GravidezRESUMO
The original PDF version of this Article contained errors in the spelling of Luiz Carlos Caires-Júnior, Uirá Souto Melo, Bruno Henrique Silva Araujo, Alessandra Soares-Schanoski, Murilo Sena Amaral, Kayque Alves Telles-Silva, Vanessa van der Linden, Helio van der Linden, João Ricardo Mendes de Oliveira, Nivia Maria Rodrigues Arrais, Joanna Goes Castro Meira, Ana Jovina Barreto Bispo, Esper Abrão Cavalheiro, and Robert Andreata-Santos, which were incorrectly given as Luiz Carlos de Caires Jr., UiráSouto Melo, Bruno Silva Henrique Araujo, Alessandra Soares Schanoski, MuriloSena Amaral, Kayque Telles Alves Silva, Vanessa Van der Linden, Helio Van der Linden, João Mendes Ricardo de Oliveira, Nivia Rodrigues Maria Arrais, Joanna Castro Goes Meira, Ana JovinaBarreto Bispo, EsperAbrão Cavalheiro, and Robert Andreata Santos. Furthermore, in both the PDF and HTML versions of the Article, the top panel of Fig. 3e was incorrectly labeled '10608-1' and should have been '10608-4', and financial support from CAPES and DECIT-MS was inadvertently omitted from the Acknowledgements section. These errors have now been corrected in both the PDF and HTML versions of the Article.
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Congenital Zika syndrome (CZS) causes early brain development impairment by affecting neural progenitor cells (NPCs). Here, we analyze NPCs from three pairs of dizygotic twins discordant for CZS. We compare by RNA-Seq the NPCs derived from CZS-affected and CZS-unaffected twins. Prior to Zika virus (ZIKV) infection the NPCs from CZS babies show a significantly different gene expression signature of mTOR and Wnt pathway regulators, key to a neurodevelopmental program. Following ZIKV in vitro infection, cells from affected individuals have significantly higher ZIKV replication and reduced cell growth. Whole-exome analysis in 18 affected CZS babies as compared to 5 unaffected twins and 609 controls excludes a monogenic model to explain resistance or increased susceptibility to CZS development. Overall, our results indicate that CZS is not a stochastic event and depends on NPC intrinsic susceptibility, possibly related to oligogenic and/or epigenetic mechanisms.
Assuntos
Encéfalo/embriologia , Expressão Gênica , Células-Tronco Neurais/metabolismo , Gêmeos Dizigóticos , Infecção por Zika virus/congênito , Encéfalo/metabolismo , Encéfalo/virologia , Brasil , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células-Tronco Pluripotentes Induzidas , Lactente , Recém-Nascido , Masculino , Células-Tronco Neurais/virologia , Análise de Sequência de RNA , Serina-Treonina Quinases TOR/genética , Via de Sinalização Wnt/genética , Infecção por Zika virus/genética , Infecção por Zika virus/virologiaRESUMO
Copy number variations (CNVs) are an important cause of ASD and those located at 15q11-q13, 16p11.2 and 22q13 have been reported as the most frequent. These CNVs exhibit variable clinical expressivity and those at 15q11-q13 and 16p11.2 also show incomplete penetrance. In the present work, through multiplex ligation-dependent probe amplification (MLPA) analysis of 531 ethnically admixed ASD-affected Brazilian individuals, we found that the combined prevalence of the 15q11-q13, 16p11.2 and 22q13 CNVs is 2.1% (11/531). Parental origin could be determined in 8 of the affected individuals, and revealed that 4 of the CNVs represent de novo events. Based on CNV prediction analysis from genome-wide SNP arrays, the size of those CNVs ranged from 206 kb to 2.27 Mb and those at 15q11-q13 were limited to the 15q13.3 region. In addition, this analysis also revealed 6 additional CNVs in 5 out of 11 affected individuals. Finally, we observed that the combined prevalence of CNVs at 15q13.3 and 22q13 in ASD-affected individuals with epilepsy (6.4%) was higher than that in ASD-affected individuals without epilepsy (1.3%; p<0.014). Therefore, our data show that the prevalence of CNVs at 15q13.3, 16p11.2 and 22q13 in Brazilian ASD-affected individuals is comparable to that estimated for ASD-affected individuals of pure or predominant European ancestry. Also, it suggests that the likelihood of a greater number of positive MLPA results might be found for the 15q13.3 and 22q13 regions by prioritizing ASD-affected individuals with epilepsy.
Assuntos
Transtornos Globais do Desenvolvimento Infantil/complicações , Transtornos Globais do Desenvolvimento Infantil/genética , Cromossomos Humanos/genética , Variações do Número de Cópias de DNA , Epilepsia/complicações , Adolescente , Sequência de Bases , Brasil , Criança , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 22/genética , Feminino , Genômica , Humanos , Masculino , Linhagem , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Cleft lip or palate (CL/P) is a common facial defect present in 1 : 700 live births and results in substantial burden to patients. There are more than 500 CL/P syndromes described, the causes of which may be single-gene mutations, chromosomopathies, and exposure to teratogens. Part of the most prevalent syndromic CL/P has known etiology. Nonsyndromic CL/P, on the other hand, is a complex disorder, whose etiology is still poorly understood. Recent genome-wide association studies have contributed to the elucidation of the genetic causes, by raising reproducible susceptibility genetic variants; their etiopathogenic roles, however, are difficult to predict, as in the case of the chromosomal region 8q24, the most corroborated locus predisposing to nonsyndromic CL/P. Knowing the genetic causes of CL/P will directly impact the genetic counseling, by estimating precise recurrence risks, and the patient management, since the patient, followup may be partially influenced by their genetic background. This paper focuses on the genetic causes of important syndromic CL/P forms (van der Woude syndrome, 22q11 deletion syndrome, and Robin sequence-associated syndromes) and depicts the recent findings in nonsyndromic CL/P research, addressing issues in the conduct of the geneticist.
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A participação dos defeitos congênitos na mortalidade infantil tornou-se mais significativa com o declínio das demais causas, por melhorias das condições socioeconômicas, o que desperta maior interesse entre os profissionais de saúde pública. De acordo com a Organização Mundial de Saúde (OMS), 7,6 milhões de crianças nascem anualmente com um defeito genético grave. O Brasil apresenta-se heterogêneo em relação às taxas de mortalidade infantil, devido às disparidades socioeconômicas, e no alcance dos programas básicos de saúde. Este trabalho objetiva conhecer e descrever os programas de saúde pública, governamentais e não-governamentais, em vigência no Brasil e, em particular, no Estado da Bahia, relacionados à prevenção, manejo e tratamento das doenças genéticas. Dentre as ações governamentais relacionadas à prevenção e monitorização das doenças genéticas, estão o Programa Nacional de Triagem Neonatal, o Programa de fortificação das farinhas com ácido fólico, a Implantação do Campo 34 na Declaração Nacional de Nascidos Vivos. Dentre as ações não-governamentais relacionadas à prevenção e monitorização das doenças genéticas, serão citados o Estudo Colaborativo Latino-americano de Malformações Congênitas e o Sistema Nacional de Informação sobre Agentes Teratogênicos. Quanto às ações relacionadas ao manejo e tratamento das doenças genéticas, existem o Programa de Osteogênese Imperfeita e o da Doença de Gaucher.