Acetilación N-terminal, acetiltransferasas y mutaciones en subunidad auxiliar NAA15 de N-terminal acetiltransferasa A, asociadas a discapacidad intelectual y trastorno del espectro autista: una revisión bibliográfica / N-terminal acetylation, acetyltransferases and variants in NAA15 auxiliary subunit of the N-terminal acetyltransferase A associated with intellectual disability and autism spectrum disorder: a literature review

Las N-terminal acetiltransferasas (NaT) son fundamentales en el desarrollo, funcionamiento y vida media celular, acetilando gran parte del proteoma humano. Entre las ocho NaT identificadas, N-terminal acetiltransferasa A (NaTA) acetila a un mayor número de sustratos, teniendo además un rol fundamental en el neurodesarrollo. Previamente, estudios han demostrado que mutaciones en la subunidad catalítica de NaTA, NAA10, se asocian con trastornos del neurodesarrollo. Sin embargo, nuevas líneas investigativas sugieren que mutaciones de la subunidad auxiliar, NAA15, también tendrían un rol importante en el desarrollo de estos trastornos. Esta revisión se realiza con el objetivo de recopilar evidencia sobre variantes de NAA15 relacionadas con Discapacidad Intelectual (DI) y Trastorno de Espectro Autista (TEA). Se consultaron fuentes actualizadas sobre acetilación N-terminal, NaT, DI y TEA y mutaciones reportadas de NAA15 y sus expresiones fenotípicas, publicadas entre 2011 y 2022. Se concluye que, aun cuando existe relación entre mutaciones de NAA15, DI y TEA, todavía es necesario esclarecer los mecanismos fisiopatológicos de estos trastornos, el rol de NaTA y el impacto de variantes de sus subunidades en las vías moleculares y el fenotipo, lo que se dificulta por razones que van desde la complejidad de estas vías hasta el elevado costo de análisis genéticos. Se sugiere continuar la investigación en esta área, para comprender las bases moleculares subyacentes a estos trastornos y el rol de las mutaciones en subunidades de NaTA, con el fin último de estudiar potenciales tratamientos que mejoren la calidad de vida de las personas con estos trastornos y sus familias.

Nt-acetyltransferases (NaT) are essential in cell development, function and half-life, catalyzing most of the human proteome. Among the eight NaTs identified, N-terminal acetyltransferase A (NaTA) acetylates a greater number of substrates, also having a fundamental role in neurodevelopment. Previously, studies have shown that mutations in the catalytic subunit of NaTA, NAA10, are associated with neurodevelopmental disorders. However, new research lines suggest that mutations of the NAA15 helper subunit also plays an important role in the development of these disorders. This review is carried out with the objective of gathering evidence on NAA15 variants related to Intellectual Disability (ID) and Autism Spectrum Disorder (ASD). Updated sources on N-terminal acetylation, N-acetyltransferases, DI and TEA and reported mutations of NAA15 and their phenotypic expressions, published between 2011 and 2022 were consulted. It is concluded that even though there is a relationship between mutations of NAA15, ID and ASD exists, it is still necessary to clarify the pathophysiological mechanisms of these disorders, the role of NaTA and the impact of variants of its subunits in the molecular pathways and in the phenotype, for reasons ranging from the complexity of these pathways to the high cost of genetic testing. It is suggested to continue research in this area, to understand the molecular bases underlying these disorders and the role of mutations in NatA subunits, with the ultimate aim of studying potential treatments that improve the quality of life of people with these disorders and their families.

La neuroanatomía y neurofisiología en la comprensión de los trastornos del espectro autista / Neuroanatomy and neurophysiology in the study of autism spectrum disorders

Introducción: Los trastornos de espectro autista se caracterizan por presentar un déficit en la interacción y comunicación social con presencia de patrones repetitivos y restrictivos de comportamiento, intereses y actividades. En ellos estarían implicadas causas genéticas, ambientales y del desarrollo del sistema nervioso central. Un mayor conocimiento de la neuroanatomía y la neurofisiología ayudaría a comprender mejor este trastorno del neurodesarrollo. Objetivo: Profundizar en el conocimiento neuroanatómico y neurofisiológico de los trastornos del espectro autista. Métodos: Se realizó una búsqueda bibliográfica acerca del tema en las bases de datos LILACS, Scopus, SciELO, Pubmed, Medigraphic. Se escogieron 13 documentos, todos correspondientes a artículos originales que abordan el tema desde diferentes aristas. De los documentos, dos fueron localizados en Scopus, uno en Pubmed, cuatro en Medigrafhic, dos en LILACS y cuatro en SciELO. Resultados: Los trastornos de espectro autista se producen por una alteración estructural y funcional de la corteza cerebral. Los estudios de neuroimágenes han demostrado las alteraciones estructurales, fundamentalmente en la corteza prefrontal y sus conexiones, principal región encefálica implicada en la regulación de la conducta social. Las técnicas de secuenciación genómica de nueva generación muestran el origen genético en casos donde los estudios previamente señalados han resultado ser normales. Conclusiones: La profundización del conocimiento neuroanatómico y neurofisiológico de los trastornos de espectro autista permiten comprenderlos mejor(AU)

Introduction: Autism spectrum disorders are characterized by social deficits and communication difficulties, as well as restrictive, repetitive behavior patterns, interests and activities. Their causes may be genetic, environmental or related to the development of the central nervous system. Broader knowledge about neuroanatomy and neurophysiology could lead to a better understanding of this neurodevelopmental disorder. Objective: Gain insight into the neuroanatomy and neurophysiology of autism spectrum disorders. Methods: A bibliographic search about the topic was conducted in the databases LILACS, Scopus, SciELO, Pubmed and Medigraphic. A total 13 documents were selected, all of which were original papers approaching the topic from different perspectives. Two of the documents were obtained from Scopus, one from Pubmed, four from Medigraphic, two from LILACS and four from SciELO. Results: Autism spectrum disorders are caused by a structural and functional alteration of the cerebral cortex. Neuroimaging studies have shown the structural alterations, which mainly occur in the prefrontal cortex and its connections, the principal encephalic region involved in social behavior regulation. New generation genomic sequencing techniques reveal a genetic origin in cases where previous studies have been normal. Conclusions: Broader knowledge about the neuroanatomy and neurophysiology of autism spectrum disorders lead to their better understanding(AU)

Estudios genéticos y neurodesarrollo: De la utilidad al modelo genético / Genetic studies and neurodevelopment. From effectiveness to genetic models]

Los avances en la genética han podido apoyar la sospecha que aportaba la experiencia clínica sobre el gran componente hereditario de la mayor parte de estos trastornos del neurodesarrollo (TND). Los estudios iniciales de heredabilidad, ligamiento o asociación evidenciaron desde los inicios la gran contribución de la variación genotípica a la clínica en general, y a los TND en particular. No debe obviarse la utilidad de los estudios genéticos en el ejercicio clínico, encaminados al diagnóstico etiológico. La mayor parte de los mismos están protocolizados en el estudio de trastornos como la discapacidad intelectual y el autismo; dentro de éstos, la hibridación por arrays cromosómicos ha aportado una mayor rentabilidad diagnóstica respecto a técnicas citogenéticas históricas (3 vs. 10% respectivamente). Sin embargo, la irrupción y rentabilidad de técnicas de genética molecular por secuenciación, particularmente la exómica y genómica en trío, analizando a padres, (tasas diagnósticas del 30-50%), están condicionando la modificación de los algoritmos genéticos en el diagnóstico de trastornos graves del neurodesarrollo. El mayor conocimiento de variantes causales de discapacidad intelectual y autismo está igualmente modificando los modelos teóricos poligénicos establecidos hasta la fecha.

Advances in genetics have been able to support the clinical suspicion on the large hereditary component of most of these neurodevelopmental disorders (NDD). Initial studies on heritability, linkage or association showed from the beginning the great contribution of genotypic variation to the clinic in general, and to NDD in particular. The effectiveness of genetic studies in clinical practice, targeted to aetiological diagnosis, should not be ignored. Most of these are protocolized in the study of disorders such as intellectual disability and autism; within these, the array comparative genomic hybridization have supported a greater diagnostic effectiveness with respect to historical cytogenetic techniques (3 vs. 10% respectively). However, the irruption and success of molecular genetic sequencing techniques, particularly the exome and genome in trio, analyzing the parents (diagnostic rates of 30-50%), are conditioning the modification of the genetic algorithms in the diagnosis of different NDD. The greater knowledge of causal variants in intellectual disability and autism is also modifying the polygenic theoretical models established to date.

Autism associated with 12q (12q24. 31-q24. 33) deletion: further report of an exceedingly rare disorder / Autismo associado à síndrome de deleção do cromossomo 12q24. 31-q24. 33: relato adicional de um distúrbio extremamente raro

ABSTRACT Chromosomal abnormalities are responsible for several congenital malformations in the world, some of these are associated to telomeric/subtelomeric deletions. The abnormalities involving the telomere of chromosome 12 are rare, with few reports of deletions involving 12q24.31 region in the literature, and, to our knowledge, only four of them in the 12q24.31-q24.33 region. We report a further case of interstitial deletion of bands 12q24.31-q24.33 associated with autism spectrum disorder. A 2-year-old boy with global developmental delay associated with multiple congenital anomalies. The Human Genome CGH Microarray 60K confirmed the diagnosis of 12q deletion syndrome. This study made a review of the current literature comparing our patient with previously reported cases. These detailed analyses contribute to the development of genotype/phenotype correlations for 12q deletions that will aid in better diagnosis and prognosis of this deletion.

RESUMO Anomalias cromossômicas são responsáveis por inúmeras malformações congênitas no mundo, algumas delas associadas a deleções teloméricas/subteloméricas. As anomalias que envolvem o telômero do cromossomo 12 são raras, com poucos relatos na literatura sobre deleções relacionados à região 12q24.31 e, até onde sabemos, apenas quatro deles na região 12q24.31-q24.33. Relatamos um outro caso de deleção intersticial das bandas 12q24.31-q24.33 associada ao transtorno do espectro do autismo. Trata-se de um menino de 2 anos de idade com atraso global no desenvolvimento associado a múltiplas anomalias congênitas. A utilização do Human Genome CGH Microarray 60K confirmou o diagnóstico da síndrome de deleção 12q. Este estudo fez uma revisão da literatura atual, comparando nosso paciente com casos previamente relatados. Estas análises detalhadas contribuem para o desenvolvimento de correlações genótipo/fenótipo para deleções 12q, que ajudam aos melhores diagnóstico e prognóstico desta deleção.

Translation, cultural adaptation, and evidence of instrument validity for a morphological examination performed in children with autism spectrum disorder / Tradução, adaptação cultural e evidência de validade de instrumento para o exame morfológico aplicado a crianças com transtorno do espectro autista

ABSTRACT Objective: For every 100 random children diagnosed with autism, at least 20 have morphological abnormalities, often associated with syndromes. Brazil does not have a standardized and validated instrument for morphological physical examination. This study aimed to translate into Brazilian Portuguese and culturally adapt the clinical signs described in the Autism Dysmorphology Measure, as well as validate the instrument in a sample of children with autism. Methods: The original instrument was translated, culturally adapted, and published in full, following traditional procedures for translation, back-translation, and terminology adaptation according to the Nomina Anatomica. The sample included 62 children from a published multicenter study, with intelligence quotient between 50-69, of both genders, with chronological age between 3-6 years. Two clinical geneticists performed the morphological physical examination, which consisted of investigating 82 characteristics assessing 12 body areas. We used Cohen's Kappa coefficient to evaluate the agreement between the two observers. Results: The final version of the instrument - translated into Brazilian Portuguese and culturally adapted - showed high agreement between the two observers. Conclusions: The translated instrument meets all international criteria, and minor anomalies and their clinical descriptions were standardized and are recognizable for physicians not specialized in genetics.

RESUMO Objetivo: Entre 100 crianças, não selecionadas, com diagnóstico de autismo, pelo menos 20 apresentam anomalias morfológicas, quase sempre associadas a síndromes. Não há no Brasil instrumento de exame físico morfológico padronizado e validado. O objetivo foi traduzir para o português do Brasil e adaptar culturalmente os sinais clínicos descritos no Autism Dysmorphology Measure, assim como procurar evidências de validade quando aplicado a uma amostra de crianças com autismo. Métodos: Foram feitas a tradução e a adaptação cultural do instrumento original, publicado na íntegra. Foram adotados os procedimentos tradicionais de tradução, retrotradução e adaptação da terminologia segundo a Nomina Anatomica. Foram incluídas na amostra 62 crianças com quociente de inteligência entre 50 e 69, de ambos os sexos, com idade cronológica entre três e seis anos, provenientes de estudo multicêntrico com os procedimentos metodológicos já publicados. O exame físico morfológico foi realizado por dois médicos geneticistas e consistiu na pesquisa de 82 características que avaliam 12 áreas corporais. Para avaliar a concordância entre os dois observadores foi utilizado o coeficiente Kappa de Cohen. Resultados: A versão final do instrumento traduzido e adaptado culturalmente ao português do Brasil mostrou alta concordância entre os dois observadores. Conclusões: O instrumento traduzido preenche todos os critérios propostos internacionalmente e o reconhecimento das anomalias menores e sua descrição clínica estão padronizados e são de fácil reconhecimento aos médicos não especialistas em genética.

Quem serão os autistas de amanhã? / ¿Quiénes serán los autistas del mañana? / Who will be the autists of tomorrow?

Para responder, da perspectiva da psicanálise, à pergunta sobre quem serão os autistas de amanhã, busca-se, em primeiro lugar, traçar linhas de como se encontram os autistas no passado. Durante o século XIX, olhar médico não podia ainda diferenciar os débeis das crianças que já estavam provavelmente desenvolvendo aquilo que hoje chamamos de autismo. Mas ouvimos seus ecos em relatos de autores da época. Para refletir sobre o momento presente, apela-se para dois operadores conceituais: o discurso e a genética, concluindo que esse novo modo de ser autista combina hoje com as novas formas de dessubjetivação que estão surgindo. O presente revela ainda que as crianças autistas, escolarizadas pelos métodos comportamentais, perdem a chance de viver na escola a verdade de sua experiência, uma experiência peculiar e única. Perdem a chance de aprender a se dizer. Em relação ao futuro, afirma- se que são muitos os devires dos autistas. Mas haverá um ponto comum a todos eles: neles o sujeito freudiano não estará, em consonância com a supressão do sujeito no mundo contemporâneo.

Para responder, desde la perspectiva del psicoanálisis, la pregunta de quiénes serán los autistas del mañana, primero buscamos trazar líneas de cómo las personas autistas son en el pasado. Durante el siglo XIX, el ojo médico aún no podía diferenciar a los débiles de los niños que probablemente ya estaban desarrollando lo que ahora llamamos autismo. Pero escuchamos sus ecos en los informes de los autores de la época. Para reflexionar sobre el momento presente, recurrimos a dos operadores conceptuales: el discurso y la genética, concluyendo que esta nueva forma de ser autista se combina hoy con las nuevas formas de desubjetivación que están surgiendo. El presente también revela que los niños autistas, educados por métodos de comportamiento, pierden la oportunidad de vivir en la escuela la verdad de su experiencia, una experiencia peculiar y única. Pierden la oportunidad de aprender a decirse a sí mismos. Con respecto al futuro, se dice que hay muchos devires de autistas. Pero habrá un punto en común para todos ellos: en ellos el sujeto freudiano no estará presente, en línea con la supresión del sujeto en el mundo contemporáneo.

To answer, from the perspective of psychoanalysis, the question of who will be the autists of tomorrow, we first seek to draw lines of how autistic people are in the past. During the nineteenth century, the medical eye could not yet differentiate children with disabilities from children who were probably already developing what we now call autism. But we hear their echoes in reports by authors of that time. To reflect on the present moment, we appeal to two conceptual operators: discourse and genetics, concluding that this new way of being autistic combines today with the new forms of desubjectivation that are emerging. The present times also reveals that autistic children, educated by behavioral methods, lose the chance to live in school the truth of their experience, a peculiar and unique experience. They lose the chance to learn to say about themselves. Regarding the future, it is said that there are many becomings of autists. But there will be a common point to all of them: in them the Freudian subject will not be present, in line with the suppression of the subject in the contemporary world.

Sueño en los trastornos del neurodesarrollo, déficit de atención e hiperactividad y en el espectro autista / Sleep in neurodevelopmental disorders

El sueño es uno de los actos fisiológicos más importantes para la estructuración funcional y anatómica de áreas del sistema nervioso central. Las alteraciones del sueño durante la infancia y su relación con trastornos del neurodesarrollo es compleja y sumam ente interesante, donde destaca la multiplicidad de causas de estos trastornos. Bajo esta premisa se realiza una revisión sobre las alteraciones del sueño en los trastornos del neurodesarrollo (TND), por déficit de atención e hiperactividad (TDAH) y del espectro autista (TEA). El sueño está presente desde la etapa fetal y va modificando su expresión en sintonía con la madurez del sistema nervioso central. Los trastornos del sueño y su relación con TDAH, TEA y otros TND son complejos, pero existen avances sobre la etiología de los mismos. Una mayor compresión de las funciones pleiotrópicas de los genes implicados en los trastornos del ciclo vigilia-sueño y en las desviaciones del desarrollo neurológico podría conducir a nuevas estrategias diagnósticas y terapéuticas de manera precoz con el fin de mejorar la calidad de vida del paciente, familiares y cuidadores.

The development and establishment of the normal sleep patterns are very important processes in the final anatomical and physiological architecture of the central nervous system. The relationship between sleep disturbances during childhood with neurodevelopmental disorders is complex and potentially synergistic. Sleep patterns are present since the fetal period but their structure and physiology is modified according with the maturation of the central nervous system. Sleep disorders and their relationship with attention deficit hyperactivity disorders(ADHD), autism spectrum disorders(ASD) and other neurodevelopmental disorders (TDN) are not well understood yet, but significant progresses have been made in understanding associations and potential etiological correlations. We reviewed sleep disturbances in NDT, in ADHD and in ASD. A greater understanding of the pleiotropic functions of the genes involved in sleep-wake cycle disorders and deviations from neurological developme nt could lead to new diagnostic and therapeut ic strategies in an early stage in order to improve the quality of life of the patient, relatives and caregivers.

Autismo: Aspectos genéticos y biológicos / Autism. Genetic and biological aspects

El autismo es un trastorno del neurodesarrollo caracterizado por compromiso en la interacción social y la comunicación, asociado a intereses restringidos y conductas estereotipadas con gran prevalencia poblacional, bases neurobiológicas y alta heredabilidad. Su etiología es heterogénea y se han reconocido numerosas bases genéticas, factores ambientales y mecanismos epigenéticos. Los avances en la genética molecular, así como los estudios epidemiológicos de grandes cohortes, han posibilitado identificar entidades médicas específicas, así como genes y factores ambientales vinculados parcial o totalmente en su patogenia. Estos conocimientos, conforme las características clínicas, permiten orientar los estudios complementarios, las conductas terapéuticas, inferir un pronóstico clínico y propiciar el asesoramiento genético familiar. En este trabajo analizamos las características clínicas de los trastornos del espectro del autismo, las entidades médicas específicas que están fuertemente relacionadas a los mismos, así como los genes reconocidos, los posibles factores ambientales y los resultados epidemiológicos que permiten el adecuado asesoramiento familiar.

Autism is a neurodevelopmental disorder characterized by commitment to social interaction and communication, associated with interests restricted and stereotyped behaviors with a high population prevalence, neurobiological bases and high heritability. Its etiology is heterogeneous, numerous genetic bases, environmental factors and epigenetic mechanisms have been recognized. Advances in molecular genetics, as well as epidemiological studies of large cohorts, have made it possible to identify specific medical entities, as well as genes and environmental factors partially or totally linked in their pathogenesis. This knowledge, according to the clinical characteristics, allows to guide the complementary studies, the therapeutic conducts, to infer a clinical prognosis and to propitiate the familiar genetic advice. In this work, the most prevalent clinical characteristics identified are described; the specific medical entities that are strongly related to autism are stated, as well as the recognized genes, the possible environmental factors and the epidemiological results that allow family counseling.

Bases neurobiológicas del autismo y modelos celulares para su estudio experimental / Neurobiological bases of autism and cellular models for its experimental study

Los trastornos del espectro autista (TEA) son una alteración funcional de la corteza cerebral, que presenta anomalías estructurales del neurodesarrollo que afectan fundamentalmente a la función sináptica y el patrón de conexiones dentro y entre columnas corticales. Desde su aspecto etiológico, el TEA tiene una importante carga genética, considerándose un desorden derivado de una combinación de mutaciones "de novo", asociadas a una predisposición derivada de variaciones comunes heredadas. Las principales anomalías genéticas asociadas a TEA implican genes que codifican proteínas de la sinapsis. Así, en pacientes con TEA se han descrito alteraciones del desarrollo inicial de las sinapsis en los circuitos de conexión entre áreas corticales de procesamiento complejo. La complejidad molecular observada en la predisposición a desarrollar un TEA, junto con la diversidad de fenotipos estructurales neuronales, ha hecho que los modelos animales reproduzcan solo parcialmente el TEA. Para avanzar en el estudio experimental se hace pues necesario desarrollar modelos más representativos, como son los modelos celulares derivados de células humanas. En las últimas décadas, el desarrollo de la biología de las células madre nos da medios para acceder a paradigmas experimentales sobre células derivadas de individuos con TEA. Actualmente, los modelos de células plutipotentes inducidas (IPs) derivadas de células humanas permiten profundizar en el estudio de las bases moleculares y celulares del TEA. Sin embargo, presentan problemas inherentes derivados de la manipulación experimental que conlleva la reprogramación de la expresión génica, por lo que otros modelos celulares se están también postulando como válidos.

Autism Spectrum Disorders (ASD) are a functional alteration of the cerebral cortex, which presents structural neurodevelopmental anomalies that affect synaptic function and the pattern of connections within and between cortical columns. From its etiological aspect, ASD has an important genetic load, considering a polygenic disorder, derived from a combination of "de novo" genetic mutations, associated to a predisposition derived from common inherited variations. The main genetic anomalies associated with ASD involve genes that encode proteins of the synapse. Thus, in patients with ASD, alterations in the initial development of the synapses have been described in the connection circuits between complex processing cortical areas. The molecular complexity observed in the predisposition to develop an ASD, together with the diversity of structural phenotypes, has made animal models reproduce only partially the ASD. To advance in the experimental study it is therefore necessary to develop representative models, such as cellular models derived from human cells. In recent decades, the advances in stem cell biology give us a way to apply experimental paradigms in cells derived from individuals with ASD. Currently, induced pluripotent cells (IPs) derived from human adult cells allow deepening the study of molecular and cellular bases of the neuronal development in humans, as well as the anomalies in this development, which give rise to disorders such as ASD. However, they present inherent problems derived from the experimental manipulation that involves the reprogramming of gene expression, therefore other models are also been explored.

Trastorno del desarrollo intelectual: Superposiciones con el trastorno del espectro autista y el trastorno por déficit de atención e hiperactividad / Intellectual developmental disability overlapping with autism spectrum disorder and attention deficit-hyperactivity disorder

Nunca dejará de ser interesante y relevante el tema de las discapacidades que abarcan la cognición y la adaptabilidad. La etiología genética tiene cada día más peso. La relación con otros trastornos del neurodesarrollo como el trastorno del espectro autista (TEA) y el trastorno por déficit de atención e hiperactividad (TDAH), es de importancia clínica, diagnóstica y terapéutica. Realizamos una revisión sobre el trastorno del desarrollo intelectual (TDI) y su implicación con el TEA y el TDAH. Desde Hipócrates hasta la actualidad los trastornos que afectan las habilidades de aprendizaje, conducta y socialización han sido sujeto de estudios y han variado sobre todo en la denominación como entidad y su percepción desde el punto de vista humano y social. La etiología del TDI en la mayoría de los casos es un enigma y los avances genéticos son la piedra angular para dilucidar el origen de este trastorno del neurodesarrollo, así como su relación con otros como el TEA y el TDAH. El trastorno del desarrollo intelectual, el más antiguo con respecto a definición, estudio y abordaje, aún presenta incógnitas sobre todo de origen etiológico. Su relación con otros trastornos del neurodesarrollo como el TEA y el TDAH es evidente por poseer áreas comunes de afectación, pudiendo ser diagnósticos coincidentes.

The subject of disabilities that include cognition and adaptability will never cease to be interesting and relevant. The genetic etiology has more weight every day. The relationship with other neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) is of clinical, diagnostic and therapeutic importance. The objective was to conduct a review of intellectual development disorder and its implication with ASD and ADHD. From Hippocrates to the present the disorders that affect learning, behavior and socialization skills have been the subject of studies and have varied, above all, in the denomination as an entity and its perception from the human and social point of view. The etiology of intellectual development disorders in most cases is an enigma and genetic advances are the cornerstone to elucidate the origin of this neurodevelopmental disorder, as well as its relationship with others such as ASD and ADHD. The disorder of intellectual development, the oldest one with respect to definition, study and approach, still presents mysteries above all of etiological origin. Its relationship with other neurodevelopmental disorders such as ASD and ADHD is evident by having common areas of involvement, which may be coincident diagnoses.

Autism spectrum disorders: an updated guide for genetic counseling / Transtornos do espectro autista: um guia atualizado para aconselhamento genético

ABSTRACT Autism spectrum disorder is a complex and genetically heterogeneous disorder, which has hampered the identification of the etiological factors in each patient and, consequently, the genetic counseling for families at risk. However, in the last decades, the remarkable advances in the knowledge of genetic aspects of autism based on genetic and molecular research, as well as the development of new molecular diagnostic tools, have substantially changed this scenario. Nowadays, it is estimated that using the currently available molecular tests, a potential underlying genetic cause can be identified in nearly 25% of cases. Combined with clinical assessment, prenatal history evaluation and investigation of other physiological aspects, an etiological explanation for the disease can be found for approximately 30 to 40% of patients. Therefore, in view of the current knowledge about the genetic architecture of autism spectrum disorder, which has contributed for a more precise genetic counseling, and of the potential benefits that an etiological investigation can bring to patients and families, molecular genetic investigation has become increasingly important. Here, we discuss the current view of the genetic architecture of autism spectrum disorder, and list the main associated genetic alterations, the available molecular tests and the key aspects for the genetic counseling of these families.

RESUMO O transtorno do espectro autista é um distúrbio complexo e geneticamente heterogêneo, o que sempre dificultou a identificação de sua etiologia em cada paciente em particular e, por consequência, o aconselhamento genético das famílias. Porém, nas últimas décadas, o acúmulo crescente de conhecimento oriundo das pesquisas sobre os aspectos genéticos e moleculares desta doença, assim como o desenvolvimento de novas ferramentas de diagnóstico molecular, tem mudado este cenário de forma substancial. Atualmente, estima-se que, por meio de testes moleculares, é possível detectar uma alteração genética potencialmente causal em cerca de 25% dos casos. Considerando-se também a avaliação clínica, a história pré-natal e a investigação de outros aspectos fisiológicos, pode-se atribuir uma etiologia para aproximadamente 30 a 40% dos pacientes. Assim, em vista do conhecimento atual sobre a arquitetura genética do transtorno do espectro autista, que tem tornado o aconselhamento genético cada vez mais preciso, e dos potenciais benefícios que a investigação etiológica pode trazer aos pacientes e familiares, tornam-se cada vez mais importantes os testes genéticos moleculares. Apresentamos aqui uma breve discussão sobre a visão atual da arquitetura genética dos transtornos do espectro autista, listando as principais alterações genéticas associadas, os testes moleculares disponíveis e os principais aspectos a se considerar para o aconselhamento genético destas famílias.

Autism in 2016: the need for answers / Autismo em 2016: necessidade de respostas

Abstract Objective: Autism spectrum disorders are lifelong and often devastating conditions that severely affect social functioning and self-sufficiency. The etiopathogenesis is presumably multifactorial, resulting from a very complex interaction between genetic and environmental factors. The dramatic increase in autism spectrum disorder prevalence observed during the last decades has led to placing more emphasis on the role of environmental factors in the etiopathogenesis. The objective of this narrative biomedical review was to summarize and discuss the results of the most recent and relevant studies about the environmental factors hypothetically involved in autism spectrum disorder etiopathogenesis. Sources: A search was performed in PubMed (United States National Library of Medicine) about the environmental factors hypothetically involved in the non-syndromic autism spectrum disorder etiopathogenesis, including: air pollutants, pesticides and other endocrine-disrupting chemicals, electromagnetic pollution, vaccinations, and diet modifications. Summary of the findings: While the association between air pollutants, pesticides and other endocrine-disrupting chemicals, and risk for autism spectrum disorder is receiving increasing confirmation, the hypothesis of a real causal relation between them needs further data. The possible pathogenic mechanisms by which environmental factors can lead to autism spectrum disorder in genetically predisposed individuals were summarized, giving particular emphasis to the increasingly important role of epigenetics. Conclusions: Future research should investigate whether there is a significant difference in the prevalence of autism spectrum disorder among nations with high and low levels of the various types of pollution. A very important goal of the research concerning the interactions between genetic and environmental factors in autism spectrum disorder etiopathogenesis is the identification of vulnerable populations, also in view of proper prevention.

Resumo Objetivo: Os transtornos do espectro autista (TEAs) são vitalícios e normalmente são doenças devastadoras que afetam gravemente o funcionamento social e a autossuficiência. A etiopatogenia é presumivelmente multifatorial, resultante de uma interação muito complexa entre fatores genéticos e ambientais. O aumento drástico na prevalência de TEAs observado nas últimas décadas levou à maior ênfase no papel dos fatores ambientais na etiopatogenia. O objetivo desta análise da narrativa biomédica foi resumir e discutir os resultados dos estudos mais recentes e relevantes sobre os fatores ambientais hipoteticamente envolvidos na etiopatogenia dos TEAs. Fontes: Foi feita uma pesquisa na Biblioteca Nacional de Medicina dos Estados Unidos (PubMed) sobre os fatores ambientais hipoteticamente envolvidos na etiopatogenia dos TEAs não sindrômicos, inclusive poluentes atmosféricos, pesticidas e outros desreguladores endócrinos, poluição eletromagnética, vacinas e alterações na dieta. Resumo dos achados: Embora a associação entre poluentes atmosféricos, pesticidas e outros desreguladores endócrinos e o risco de TEA tenha recebido cada vez mais confirmações, a hipótese de uma relação causal real entre eles ainda precisa de mais dados. Os possíveis mecanismos patogênicos por meio dos quais os fatores ambientais podem causar TEA em indivíduos geneticamente predispostos foram resumidos, com ênfase especial no papel cada vez mais importante da epigenética. Conclusões: Futuras pesquisas devem investigar se há uma diferença significativa na prevalência de TEA entre nações com níveis altos e baixos de vários tipos de poluição. Um objetivo muito importante da pesquisa a respeito das interações entre fatores genéticos e ambientais na etiopatogenia do TEA é a identificação de populações vulneráveis, também em virtude da prevenção adequada.

Déficit atencional con hiperactividad: trastorno multicausal de la conducta, con heredabilidad y comorbilidad genética moderadas / Heritability and genetic comorbidity of attention deficit disorder with hyperactivity

This review aims to summarize information about the genetic etiology of attention deficit disorder with hyperactivity (ADHD), with particular reference to the contributions of our research group. We also discuss the genetic comorbidity estimated from genome-wide single nucleotide polymorphisms (SNP´s) between ADHD and major psychiatric disorders such as schizophrenia (E), major depressive disorder (MDD), bipolar disorder (BD) and autism spectrum disorders (ASD). A high genetic comorbidity was found between E and BD (46%), a moderate comorbidity between MDD and E, MDD and BD and MDD and ADHD (18%, 22% and 10% respectively) and a low comorbidity between E and ASD (2.5%). Furthermore, we show evidence concerning the genetic determination of psychiatric diseases, which is significantly lower when it is estimated from genome-wide SNP´s rather than using traditional quantitative genetic methodology (ADHD = E = 23%, BD = 25%, MDD = 21% and ASD = 17%). From an evolutionary perspective, we suggest that behavioral traits such as hyperactivity, inattention and impulsivity, which play a role in ADHD and perhaps also other hereditary traits which are part of major psychiatric disorders, could have had a high adaptive value during the early stages of the evolution of Homo sapiens. However, they became progressively less adaptive and definitively disadvantageous, to the extreme that they are involved in frequently diagnosed major psychiatric disorders.

Teoria da mente em pais de pessoas com autismo: uma análise comparativa / Theory of mind for parents of people with autism: a comparative analysis

O autismo pode ser definido como uma síndrome comportamental heterogênea em termos genéticos e de diagnóstico. Esta heterogeneidade dificulta a realização de estudos genéticos sobre o tema. Um dos endofenótipos candidatos do autismo é a teoria da mente. O objetivo deste estudo foi avaliar a capacidade da teoria da mente em pais de crianças com autismo. Foram avaliados 90 participantes: 30 pais de crianças com autismo, 30 pais de crianças com síndrome de Down e 30 pais de crianças com desenvolvimento típico. Os instrumentos utilizados foram o Eyes Test, para avaliar habilidades de decodificação, e o Unexpected Outcomes Task, para medir o raciocínio dedutivo. Os resultados não indicam diferenças significativas entre os grupos na habilidade de decodificação. No entanto, eles indicam a existência de déficits na capacidade de dedução da teoria da mente. Esse déficit parece ser mais pronunciado em mães de crianças com autismo, em comparação com grupos de mães de crianças com síndrome de Down e mães de crianças com desenvolvimento típico. Mais estudos são necessários para esclarecer melhor a relação entre teoria da mente e autismo. (AU)

Autism can be defined as a heterogeneous behavioral syndrome in both genetic and diagnostic terms. This heterogeneity poses difficulties in conducting genetic studies on the topic. A candidate endophenotype of autism is theory of mind. The goal of this study was to evaluate the ability of theory of mind in parents of children with autism. We evaluated 90 participants: 30 parents of children with autism, 30 parents of children with Down syndrome and 30 parents of typically developing children. The instruments used were the Eyes Test, to assess decoding skills, and the Unexpected Outcomes Task, to measure deductive reasoning. The results do not indicate significant differences between groups in theory of mind decoding. However, they indicate the existence of deficits in the theory of mind reasoning. These deficits seem to be more pronounced in mothers of children with autism, compared to groups of mothers of children with Down syndrome and mothers of typically developing children. Further studies are needed to better clarify the relationship between theory of mind and autism. (AU)