Germline homozygous missense DEPDC5 variants cause severe refractory early-onset epilepsy, macrocephaly and bilateral polymicrogyria.

DEPDC5 (DEP Domain-Containing Protein 5) encodes an inhibitory component of the mammalian target of rapamycin (mTOR) pathway and is commonly implicated in sporadic and familial focal epilepsies, both non-lesional and in association with focal cortical dysplasia. Germline pathogenic variants are typically heterozygous and inactivating. We describe a novel phenotype caused by germline biallelic missense variants in DEPDC5. Cases were identified clinically. Available records, including magnetic resonance imaging and electroencephalography, were reviewed. Genetic testing was performed by whole exome and whole-genome sequencing and cascade screening. In addition, immunohistochemistry was performed on skin biopsy. The phenotype was identified in nine children, eight of which are described in detail herein. Six of the children were of Irish Traveller, two of Tunisian and one of Lebanese origin. The Irish Traveller children shared the same DEPDC5 germline homozygous missense variant (p.Thr337Arg), whereas the Lebanese and Tunisian children shared a different germline homozygous variant (p.Arg806Cys). Consistent phenotypic features included extensive bilateral polymicrogyria, congenital macrocephaly and early-onset refractory epilepsy, in keeping with other mTOR-opathies. Eye and cardiac involvement and severe neutropenia were also observed in one or more patients. Five of the children died in infancy or childhood; the other four are currently aged between 5 months and 6 years. Skin biopsy immunohistochemistry was supportive of hyperactivation of the mTOR pathway. The clinical, histopathological and genetic evidence supports a causal role for the homozygous DEPDC5 variants, expanding our understanding of the biology of this gene.

Recessive PRDM13 mutations cause fatal perinatal brainstem dysfunction with cerebellar hypoplasia and disrupt Purkinje cell differentiation.

Pontocerebellar hypoplasias (PCHs) are congenital disorders characterized by hypoplasia or early atrophy of the cerebellum and brainstem, leading to a very limited motor and cognitive development. Although over 20 genes have been shown to be mutated in PCHs, a large proportion of affected individuals remains undiagnosed. We describe four families with children presenting with severe neonatal brainstem dysfunction and pronounced deficits in cognitive and motor development associated with four different bi-allelic mutations in PRDM13, including homozygous truncating variants in the most severely affected individuals. Brain MRI and fetopathological examination revealed a PCH-like phenotype, associated with major hypoplasia of inferior olive nuclei and dysplasia of the dentate nucleus. Notably, histopathological examinations highlighted a sparse and disorganized Purkinje cell layer in the cerebellum. PRDM13 encodes a transcriptional repressor known to be critical for neuronal subtypes specification in the mouse retina and spinal cord but had not been implicated, so far, in hindbrain development. snRNA-seq data mining and in situ hybridization in humans show that PRDM13 is expressed at early stages in the progenitors of the cerebellar ventricular zone, which gives rise to cerebellar GABAergic neurons, including Purkinje cells. We also show that loss of function of prdm13 in zebrafish leads to a reduction in Purkinje cells numbers and a complete absence of the inferior olive nuclei. Altogether our data identified bi-allelic mutations in PRDM13 as causing a olivopontocerebellar hypoplasia syndrome and suggest that early deregulations of the transcriptional control of neuronal fate specification could contribute to a significant number of cases.

THUMPD1 bi-allelic variants cause loss of tRNA acetylation and a syndromic neurodevelopmental disorder.

Covalent tRNA modifications play multi-faceted roles in tRNA stability, folding, and recognition, as well as the rate and fidelity of translation, and other cellular processes such as growth, development, and stress responses. Mutations in genes that are known to regulate tRNA modifications lead to a wide array of phenotypes and diseases including numerous cognitive and neurodevelopmental disorders, highlighting the critical role of tRNA modification in human disease. One such gene, THUMPD1, is involved in regulating tRNA N4-acetylcytidine modification (ac4C), and recently was proposed as a candidate gene for autosomal-recessive intellectual disability. Here, we present 13 individuals from 8 families who harbor rare loss-of-function variants in THUMPD1. Common phenotypic findings included global developmental delay, speech delay, moderate to severe intellectual deficiency, behavioral abnormalities such as angry outbursts, facial dysmorphism, and ophthalmological abnormalities. We demonstrate that the bi-allelic variants identified cause loss of function of THUMPD1 and that this defect results in a loss of ac4C modification in small RNAs, and of individually purified tRNA-Ser-CGA. We further corroborate this effect by showing a loss of tRNA acetylation in two CRISPR-Cas9-generated THUMPD1 KO cell lines. In addition, we also show the resultant amino acid substitution that occurs in a missense THUMPD1 allele identified in an individual with compound heterozygous variants results in a marked decrease in THUMPD1 stability and RNA-binding capacity. Taken together, these results suggest that the lack of tRNA acetylation due to THUMPD1 loss of function results in a syndromic form of intellectual disability associated with developmental delay, behavioral abnormalities, hearing loss, and facial dysmorphism.

Bi-allelic LETM1 variants perturb mitochondrial ion homeostasis leading to a clinical spectrum with predominant nervous system involvement.

Leucine zipper-EF-hand containing transmembrane protein 1 (LETM1) encodes an inner mitochondrial membrane protein with an osmoregulatory function controlling mitochondrial volume and ion homeostasis. The putative association of LETM1 with a human disease was initially suggested in Wolf-Hirschhorn syndrome, a disorder that results from de novo monoallelic deletion of chromosome 4p16.3, a region encompassing LETM1. Utilizing exome sequencing and international gene-matching efforts, we have identified 18 affected individuals from 11 unrelated families harboring ultra-rare bi-allelic missense and loss-of-function LETM1 variants and clinical presentations highly suggestive of mitochondrial disease. These manifested as a spectrum of predominantly infantile-onset (14/18, 78%) and variably progressive neurological, metabolic, and dysmorphic symptoms, plus multiple organ dysfunction associated with neurodegeneration. The common features included respiratory chain complex deficiencies (100%), global developmental delay (94%), optic atrophy (83%), sensorineural hearing loss (78%), and cerebellar ataxia (78%) followed by epilepsy (67%), spasticity (53%), and myopathy (50%). Other features included bilateral cataracts (42%), cardiomyopathy (36%), and diabetes (27%). To better understand the pathogenic mechanism of the identified LETM1 variants, we performed biochemical and morphological studies on mitochondrial K+/H+ exchange activity, proteins, and shape in proband-derived fibroblasts and muscles and in Saccharomyces cerevisiae, which is an important model organism for mitochondrial osmotic regulation. Our results demonstrate that bi-allelic LETM1 variants are associated with defective mitochondrial K+ efflux, swollen mitochondrial matrix structures, and loss of important mitochondrial oxidative phosphorylation protein components, thus highlighting the implication of perturbed mitochondrial osmoregulation caused by LETM1 variants in neurological and mitochondrial pathologies.

Bi-allelic variants in WNT7B disrupt the development of multiple organs in humans.

BACKGROUND: Pulmonary hypoplasia, Diaphragmatic anomalies, Anophthalmia/microphthalmia and Cardiac defects delineate the PDAC syndrome. We aim to identify the cause of PDAC syndrome in patients who do not carry pathogenic variants in RARB and STRA6, which have been previously associated with this disorder. METHODS: We sequenced the exome of patients with unexplained PDAC syndrome and performed functional validation of candidate variants. RESULTS: We identified bi-allelic variants in WNT7B in fetuses with PDAC syndrome from two unrelated families. In one family, the fetus was homozygous for the c.292C>T (p.(Arg98*)) variant whereas the fetuses from the other family were compound heterozygous for the variants c.225C>G (p.(Tyr75*)) and c.562G>A (p.(Gly188Ser)). Finally, a molecular autopsy by proxy in a consanguineous couple that lost two babies due to lung hypoplasia revealed that both parents carry the p.(Arg98*) variant. Using a WNT signalling canonical luciferase assay, we demonstrated that the identified variants are deleterious. In addition, we found that wnt7bb mutant zebrafish display a defect of the swimbladder, an air-filled organ that is a structural homolog of the mammalian lung, suggesting that the function of WNT7B has been conserved during evolution for the development of these structures. CONCLUSION: Our findings indicate that defective WNT7B function underlies a form of lung hypoplasia that is associated with the PDAC syndrome, and provide evidence for involvement of the WNT-ß-catenin pathway in human lung, tracheal, ocular, cardiac, and renal development.

Recurrent De Novo NAHR Reciprocal Duplications in the ATAD3 Gene Cluster Cause a Neurogenetic Trait with Perturbed Cholesterol and Mitochondrial Metabolism.

Recent studies have identified both recessive and dominant forms of mitochondrial disease that result from ATAD3A variants. The recessive form includes subjects with biallelic deletions mediated by non-allelic homologous recombination. We report five unrelated neonates with a lethal metabolic disorder characterized by cardiomyopathy, corneal opacities, encephalopathy, hypotonia, and seizures in whom a monoallelic reciprocal duplication at the ATAD3 locus was identified. Analysis of the breakpoint junction fragment indicated that these 67 kb heterozygous duplications were likely mediated by non-allelic homologous recombination at regions of high sequence identity in ATAD3A exon 11 and ATAD3C exon 7. At the recombinant junction, the duplication allele produces a fusion gene derived from ATAD3A and ATAD3C, the protein product of which lacks key functional residues. Analysis of fibroblasts derived from two affected individuals shows that the fusion gene product is expressed and stable. These cells display perturbed cholesterol and mitochondrial DNA organization similar to that observed for individuals with severe ATAD3A deficiency. We hypothesize that the fusion protein acts through a dominant-negative mechanism to cause this fatal mitochondrial disorder. Our data delineate a molecular diagnosis for this disorder, extend the clinical spectrum associated with structural variation at the ATAD3 locus, and identify a third mutational mechanism for ATAD3 gene cluster variants. These results further affirm structural variant mutagenesis mechanisms in sporadic disease traits, emphasize the importance of copy number analysis in molecular genomic diagnosis, and highlight some of the challenges of detecting and interpreting clinically relevant rare gene rearrangements from next-generation sequencing data.

Mutations in PIGB Cause an Inherited GPI Biosynthesis Defect with an Axonal Neuropathy and Metabolic Abnormality in Severe Cases.

Proteins anchored to the cell surface via glycosylphosphatidylinositol (GPI) play various key roles in the human body, particularly in development and neurogenesis. As such, many developmental disorders are caused by mutations in genes involved in the GPI biosynthesis and remodeling pathway. We describe ten unrelated families with bi-allelic mutations in PIGB, a gene that encodes phosphatidylinositol glycan class B, which transfers the third mannose to the GPI. Ten different PIGB variants were found in these individuals. Flow cytometric analysis of blood cells and fibroblasts from the affected individuals showed decreased cell surface presence of GPI-anchored proteins. Most of the affected individuals have global developmental and/or intellectual delay, all had seizures, two had polymicrogyria, and four had a peripheral neuropathy. Eight children passed away before four years old. Two of them had a clinical diagnosis of DOORS syndrome (deafness, onychodystrophy, osteodystrophy, mental retardation, and seizures), a condition that includes sensorineural deafness, shortened terminal phalanges with small finger and toenails, intellectual disability, and seizures; this condition overlaps with the severe phenotypes associated with inherited GPI deficiency. Most individuals tested showed elevated alkaline phosphatase, which is a characteristic of the inherited GPI deficiency but not DOORS syndrome. It is notable that two severely affected individuals showed 2-oxoglutaric aciduria, which can be seen in DOORS syndrome, suggesting that severe cases of inherited GPI deficiency and DOORS syndrome might share some molecular pathway disruptions.

HK1 haemolytic anaemia in association with a neurological phenotype and co-existing CEP290 Meckel-Gruber in a Romani family.

HK1 deficient Haemolytic Anaemia in association with a Neurological Phenotype & co-existing Meckel-Gruber due to CEP290 in a Romani family.

Heterozygous variants in ZBTB7A cause a neurodevelopmental disorder associated with symptomatic overgrowth of pharyngeal lymphoid tissue, macrocephaly, and elevated fetal hemoglobin.

By clinical whole exome sequencing, we identified 12 individuals with ages 3 to 37 years, including three individuals from the same family, with a consistent phenotype of intellectual disability (ID), macrocephaly, and overgrowth of adenoid tissue. All 12 individuals harbored a rare heterozygous variant in ZBTB7A which encodes the transcription factor Zinc finger and BTB-domain containing protein 7A, known to play a role in lympho- and hematopoiesis. ID was generally mild. Fetal hemoglobin (HbF) fraction was elevated 2.2%-11.2% (reference value <2% in individuals > 6 months) in four of the five individuals for whom results were available. Ten of twelve individuals had undergone surgery at least once for lymphoid hypertrophy limited to the pharynx. In the most severely affected individual (individual 1), airway obstruction resulted in 17 surgical procedures before the age of 13 years. Sleep apnea was present in 8 of 10 individuals. In the nine unrelated individuals, ZBTB7A variants were novel and de novo. The six frameshift/nonsense and four missense variants were spread throughout the gene. This is the first report of a cohort of individuals with this novel syndromic neurodevelopmental disorder.

DLG5 variants are associated with multiple congenital anomalies including ciliopathy phenotypes.

BACKGROUND: Cilia are dynamic cellular extensions that generate and sense signals to orchestrate proper development and tissue homeostasis. They rely on the underlying polarisation of cells to participate in signalling. Cilia dysfunction is a well-known cause of several diseases that affect multiple organ systems including the kidneys, brain, heart, respiratory tract, skeleton and retina. METHODS: Among individuals from four unrelated families, we identified variants in discs large 5 (DLG5) that manifested in a variety of pathologies. In our proband, we also examined patient tissues. We depleted dlg5 in Xenopus tropicalis frog embryos to generate a loss-of-function model. Finally, we tested the pathogenicity of DLG5 patient variants through rescue experiments in the frog model. RESULTS: Patients with variants of DLG5 were found to have a variety of phenotypes including cystic kidneys, nephrotic syndrome, hydrocephalus, limb abnormalities, congenital heart disease and craniofacial malformations. We also observed a loss of cilia in cystic kidney tissue of our proband. Knockdown of dlg5 in Xenopus embryos recapitulated many of these phenotypes and resulted in a loss of cilia in multiple tissues. Unlike introduction of wildtype DLG5 in frog embryos depleted of dlg5, introduction of DLG5 patient variants was largely ineffective in restoring proper ciliation and tissue morphology in the kidney and brain suggesting that the variants were indeed detrimental to function. CONCLUSION: These findings in both patient tissues and Xenopus shed light on how mutations in DLG5 may lead to tissue-specific manifestations of disease. DLG5 is essential for cilia and many of the patient phenotypes are in the ciliopathy spectrum.

Truncating variants in the SHANK1 gene are associated with a spectrum of neurodevelopmental disorders.

PURPOSE: In this study, we aimed to characterize the clinical phenotype of a SHANK1-related disorder and define the functional consequences of SHANK1 truncating variants. METHODS: Exome sequencing (ES) was performed for six individuals who presented with neurodevelopmental disorders. Individuals were ascertained with the use of GeneMatcher and Database of Chromosomal Imbalance and Phenotype in Humans Using Ensembl Resources (DECIPHER). We evaluated potential nonsense-mediated decay (NMD) of two variants by making knock-in cell lines of endogenous truncated SHANK1, and expressed the truncated SHANK1 complementary DNA (cDNA) in HEK293 cells and cultured hippocampal neurons to examine the proteins. RESULTS: ES detected de novo truncating variants in SHANK1 in six individuals. Evaluation of NMD resulted in stable transcripts, and the truncated SHANK1 completely lost binding with Homer1, a linker protein that binds to the C-terminus of SHANK1. These variants may disrupt protein-protein networks in dendritic spines. Dispersed localization of the truncated SHANK1 variants within the spine and dendritic shaft was also observed when expressed in neurons, indicating impaired synaptic localization of truncated SHANK1. CONCLUSION: This report expands the clinical spectrum of individuals with truncating SHANK1 variants and describes the impact these variants may have on the pathophysiology of neurodevelopmental disorders.

Study of Acute Liver Failure in Children Using Next Generation Sequencing Technology.

OBJECTIVE: To use next generation sequencing (NGS) technology to identify undiagnosed, monogenic diseases in a cohort of children who suffered from acute liver failure (ALF) without an identifiable etiology. STUDY DESIGN: We identified 148 under 10 years of age admitted to King's College Hospital, London, with ALF of indeterminate etiology between 2000 and 2018. A custom NGS panel of 64 candidate genes known to cause ALF and/or metabolic liver disease was constructed. Targeted sequencing was carried out on 41 children in whom DNA samples were available. Trio exome sequencing was performed on 4 children admitted during 2019. A comparison of the clinical characteristics of those identified with biallelic variants against those without biallelic variants was then made. RESULTS: Homozygous and compound heterozygous variants were identified in 8 out of 41 children (20%) and 4 out of 4 children (100%) in whom targeted and exome sequencing were carried out, respectively. The genes involved were NBAS (3 children); DLD (2 children); and CPT1A, FAH, LARS1, MPV17, NPC1, POLG, SUCLG1, and TWINK (1 each). The 12 children who were identified with biallelic variants were younger at presentation and more likely to die in comparison with those who did not: median age at presentation of 3 months and 30 months and survival rate 75% and 97%, respectively. CONCLUSIONS: NGS was successful in identifying several specific etiologies of ALF. Variants in NBAS and mitochondrial DNA maintenance genes were the most common findings. In the future, a rapid sequencing NGS workflow could help in reaching a timely diagnosis and facilitate clinical decision making in children with ALF.

Rapid exome sequencing: revolutionises the management of acutely unwell neonates.

Diagnosing acutely unwell infants with a potential genetic diagnosis can be challenging for healthcare professionals. Evidence suggests that up to 13% of critically unwell infants on the neonatal intensive care unit (NICU) have an underlying molecular diagnosis and when identified directly affects treatment decisions in 83%. On 1st October 2019, the National Health Service England (NHSE) launched a nationally commissioned service so that rapid whole-exome sequencing can be offered to critically unwell babies and children with a likely monogenic disorder who are admitted to NICU and paediatric intensive care unit (PICU). We present 7 cases from two neonatal units in the West Midlands (UK), where rapid exome sequencing has revealed a genetic diagnosis. Early genetic diagnosis in this cohort has influenced management in all (100%) cases, and in 57% (4 in 7 cases), it has helped in the decision to reorientate care. In some cases, early diagnosis has reduced the need for invasive and unnecessary investigations and avoided the need for post-mortem investigations. The genetic diagnosis has helped in counselling the families regarding the recurrence risk for future pregnancies. In some cases, this has provided parents with the reassurance of a low recurrence. In others, it has resulted in the offer of prenatal diagnosis or assisted conception technologies. What is Known: • Rapid whole-exome sequencing was commissioned in the UK in October 2019. • It is available for critically unwell babies with a likely monogenic aetiology. What is New: • It helps management planning for rare genetic disorders and future pregnancies counselling. • It can reduce the need for invasive investigations and overall intensive care costs.

Recurrent TTN metatranscript-only c.39974-11T>G splice variant associated with autosomal recessive arthrogryposis multiplex congenita and myopathy.

We present eight families with arthrogryposis multiplex congenita and myopathy bearing a TTN intron 213 extended splice-site variant (NM_001267550.1:c.39974-11T>G), inherited in trans with a second pathogenic TTN variant. Muscle-derived RNA studies of three individuals confirmed mis-splicing induced by the c.39974-11T>G variant; in-frame exon 214 skipping or use of a cryptic 3' splice-site effecting a frameshift. Confounding interpretation of pathogenicity is the absence of exons 213-217 within the described skeletal muscle TTN N2A isoform. However, RNA-sequencing from 365 adult human gastrocnemius samples revealed that 56% specimens predominantly include exons 213-217 in TTN transcripts (inclusion rate ≥66%). Further, RNA-sequencing of five fetal muscle samples confirmed that 4/5 specimens predominantly include exons 213-217 (fifth sample inclusion rate 57%). Contractures improved significantly with age for four individuals, which may be linked to decreased expression of pathogenic fetal transcripts. Our study extends emerging evidence supporting a vital developmental role for TTN isoforms containing metatranscript-only exons.

Expanding the phenotypic spectrum of IFT81: Associated ciliopathy syndrome.

Short-rib polydactyly syndromes are a heterogeneous group of disorders characterized by narrow thorax with short ribs, polydactyly and often other visceral and skeletal malformations. To date there have only been six reported patients with homozygous and compound heterozygous variants in IFT81, causing a short-rib thoracic dysplasia, with, or without, polydactyly (SRTD19: OMIM 617895). IFT81 is a protein integral to the core of the intraflagellar transport complex B (IFT-B), which is involved in anterograde transport in the cilium. We describe the case of a male infant with compound heterozygous variants in IFT81, who presented with short long bones, a narrow thorax, polydactyly, and multiple malformations. Three novel clinical features are reported including complete situs inversus, micropenis, and rectal atresia, which have not previously been associated with variants in IFT81. We reviewed the literature and identified the most consistent clinical features associated with this rare ciliopathy syndrome. We postulate that dolichocephaly and sagittal craniosynostosis may be associated with this condition, and provide a clue to considering IFT81 as the causative gene when deciphering complex ciliopathies.

NAD(P)HX dehydratase (NAXD) deficiency: a novel neurodegenerative disorder exacerbated by febrile illnesses.

Physical stress, including high temperatures, may damage the central metabolic nicotinamide nucleotide cofactors [NAD(P)H], generating toxic derivatives [NAD(P)HX]. The highly conserved enzyme NAD(P)HX dehydratase (NAXD) is essential for intracellular repair of NAD(P)HX. Here we present a series of infants and children who suffered episodes of febrile illness-induced neurodegeneration or cardiac failure and early death. Whole-exome or whole-genome sequencing identified recessive NAXD variants in each case. Variants were predicted to be potentially deleterious through in silico analysis. Reverse-transcription PCR confirmed altered splicing in one case. Subject fibroblasts showed highly elevated concentrations of the damaged cofactors S-NADHX, R-NADHX and cyclic NADHX. NADHX accumulation was abrogated by lentiviral transduction of subject cells with wild-type NAXD. Subject fibroblasts and muscle biopsies showed impaired mitochondrial function, higher sensitivity to metabolic stress in media containing galactose and azide, but not glucose, and decreased mitochondrial reactive oxygen species production. Recombinant NAXD protein harbouring two missense variants leading to the amino acid changes p.(Gly63Ser) and p.(Arg608Cys) were thermolabile and showed a decrease in Vmax and increase in KM for the ATP-dependent NADHX dehydratase activity. This is the first study to identify pathogenic variants in NAXD and to link deficient NADHX repair with mitochondrial dysfunction. The results show that NAXD deficiency can be classified as a metabolite repair disorder in which accumulation of damaged metabolites likely triggers devastating effects in tissues such as the brain and the heart, eventually leading to early childhood death.

Diagnosis of lethal or prenatal-onset autosomal recessive disorders by parental exome sequencing.

OBJECTIVE: Rare genetic disorders resulting in prenatal or neonatal death are genetically heterogeneous, but testing is often limited by the availability of fetal DNA, leaving couples without a potential prenatal test for future pregnancies. We describe our novel strategy of exome sequencing parental DNA samples to diagnose recessive monogenic disorders in an audit of the first 50 couples referred. METHOD: Exome sequencing was carried out in a consecutive series of 50 couples who had 1 or more pregnancies affected with a lethal or prenatal-onset disorder. In all cases, there was insufficient DNA for exome sequencing of the affected fetus. Heterozygous rare variants (MAF < 0.001) in the same gene in both parents were selected for analysis. Likely, disease-causing variants were tested in fetal DNA to confirm co-segregation. RESULTS: Parental exome analysis identified heterozygous pathogenic (or likely pathogenic) variants in 24 different genes in 26/50 couples (52%). Where 2 or more fetuses were affected, a genetic diagnosis was obtained in 18/29 cases (62%). In most cases, the clinical features were typical of the disorder, but in others, they result from a hypomorphic variant or represent the most severe form of a variable phenotypic spectrum. CONCLUSION: We conclude that exome sequencing of parental samples is a powerful strategy with high clinical utility for the genetic diagnosis of lethal or prenatal-onset recessive disorders. © 2017 The Authors Prenatal Diagnosis published by John Wiley & Sons Ltd.

["Revealing in the gerund": secrecy and stigma in practices of care for children and adolescents living with HIV/Aids]. / "Revelando", no gerúndio: segredo e estigma nas práticas de cuidado às crianças e adolescentes vivendo com HIV/Aids.

This article analyzes practices of care and the HIV diagnosis disclosure process to children and adolescents living with HIV/AIDS. A case study was conducted in an outpatient clinic located in a public hospital in Rio de Janeiro through participant observation, semi-structured interviews with health professionals, and the consultation of documents produced by the professionals. The analysis, based on the sociology of Simmel and Goffman, points to the revelation of the diagnosis as a hallmark that accompanies all the care established with users and sheds light on issues such as secrecy, stigma and the possible understandings about the health condition established. As a result, institutionalized relationships contribute to a progressive contact with the condition of bearing a stigma and enable phases of a patient's life protected by information to exist.

O artigo analisa as práticas de cuidado e o processo de revelação do diagnóstico a crianças e adolescentes vivendo com HIV/Aids. Foi realizado um estudo de caso em um ambulatório localizado em um hospital público do Rio de Janeiro (RJ), através de observação participante, entrevistas semiestruturadas com profissionais de saúde e consulta a documentos produzidos pelos profissionais. A análise, baseada na sociologia de Simmel e Goffman, aponta a revelação do diagnóstico como uma marca que acompanha todo o cuidado estabelecido com os usuários e dá luz a questões como o segredo, o estigma e as possíveis compreensões acerca da condição de saúde estabelecidas. Com isso, as relações institucionalizadas contribuem para um progressivo contato com a condição de portador de um estigma e fazem existir fases de uma carreira de doente protegido pela informação.

Clinical findings and structural analysis involving a patient with a novel KLHL15 variant.

A de novo novel variant of uncertain significance p. (Arg532del) in the KLHL15 gene was identified by trio exome analysis in a child with global developmental delay, coarse facial features, repetitive behaviour, increased fatigability, poor feeding and gastro-oesophageal reflux. Comparative modelling and structural analysis were performed to gain insight into the effects of the variant on KLHL15 protein structure and function, with a view to aiding variant classification. The p. (Arg532del) variant affects a highly conserved residue within one of the Kelch repeats of the KLHL15 protein. This residue contributes to the stability of loop regions at the substrate binding surface of the protein; comparative modelling of the variant protein predicts altered topology at this surface, including at residue Tyr552, which is known to be important for substrate binding. We propose that it is highly probable that the p. (Arg532del) variant has a deleterious impact on KLHL15 structure, leading to a reduced level of protein function in vivo.

Penetrance of pathogenic genetic variants associated with premature ovarian insufficiency.

Premature ovarian insufficiency (POI) affects 1% of women and is a leading cause of infertility. It is often considered to be a monogenic disorder, with pathogenic variants in ~100 genes described in the literature. We sought to systematically evaluate the penetrance of variants in these genes using exome sequence data in 104,733 women from the UK Biobank, 2,231 (1.14%) of whom reported at natural menopause under the age of 40 years. We found limited evidence to support any previously reported autosomal dominant effect. For nearly all heterozygous effects on previously reported POI genes, we ruled out even modest penetrance, with 99.9% (13,699 out of 13,708) of all protein-truncating variants found in reproductively healthy women. We found evidence of haploinsufficiency effects in several genes, including TWNK (1.54 years earlier menopause, P = 1.59 × 10-6) and SOHLH2 (3.48 years earlier menopause, P = 1.03 × 10-4). Collectively, our results suggest that, for the vast majority of women, POI is not caused by autosomal dominant variants either in genes previously reported or currently evaluated in clinical diagnostic panels. Our findings, plus previous studies, suggest that most POI cases are likely oligogenic or polygenic in nature, which has important implications for future clinical genetic studies, and genetic counseling for families affected by POI.