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1.
Nat Commun ; 15(1): 3530, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664422

RESUMO

This paper explicates a solution to building correspondences between molecular-scale transcriptomics and tissue-scale atlases. This problem arises in atlas construction and cross-specimen/technology alignment where specimens per emerging technology remain sparse and conventional image representations cannot efficiently model the high dimensions from subcellular detection of thousands of genes. We address these challenges by representing spatial transcriptomics data as generalized functions encoding position and high-dimensional feature (gene, cell type) identity. We map onto low-dimensional atlas ontologies by modeling regions as homogeneous random fields with unknown transcriptomic feature distribution. We solve simultaneously for the minimizing geodesic diffeomorphism of coordinates through LDDMM and for these latent feature densities. We map tissue-scale mouse brain atlases to gene-based and cell-based transcriptomics data from MERFISH and BARseq technologies and to histopathology and cross-species atlases to illustrate integration of diverse molecular and cellular datasets into a single coordinate system as a means of comparison and further atlas construction.


Assuntos
Atlas como Assunto , Encéfalo , Transcriptoma , Animais , Encéfalo/metabolismo , Camundongos , Transcriptoma/genética , Processamento de Imagem Assistida por Computador/métodos , Perfilação da Expressão Gênica/métodos , Humanos
2.
mSystems ; 9(2): e0111023, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38197647

RESUMO

Host-microbe interactions constitute dynamical systems that can be represented by mathematical formulations that determine their dynamic nature and are categorized as deterministic, stochastic, or chaotic. Knowing the type of dynamical interaction is essential for understanding the system under study. Very little experimental work has been done to determine the dynamical characteristics of host-microbe interactions, and its study poses significant challenges. The most straightforward experimental outcome involves an observation of time to death upon infection. However, in measuring this outcome, the internal parameters and the dynamics of each particular host-microbe interaction in a population of interactions are hidden from the experimentalist. To investigate whether a time-to-death (time-to-event) data set provides adequate information for searching for chaotic signatures, we first determined our ability to detect chaos in simulated data sets of time-to-event measurements and successfully distinguished the time-to-event distribution of a chaotic process from a comparable stochastic one. To do so, we introduced an inversion measure to test for a chaotic signature in time-to-event distributions. Next, we searched for chaos in the time-to-death of Caenorhabditis elegans and Drosophila melanogaster infected with Pseudomonas aeruginosa or Pseudomonas entomophila, respectively. We found suggestions of chaotic signatures in both systems but caution that our results are preliminary and highlight the need for more fine-grained and larger data sets in determining dynamical characteristics. If validated, chaos in host-microbe interactions would have important implications for the occurrence and outcome of infectious diseases, the reproducibility of experiments in the field of microbial pathogenesis, and the prediction of microbial threats.IMPORTANCEIs microbial pathogenesis a predictable scientific field? At a time when we are dealing with coronavirus disease 2019, there is intense interest in knowing about the epidemic potential of other microbial threats and new emerging infectious diseases. To know whether microbial pathogenesis will ever be a predictable scientific field requires knowing whether a host-microbe interaction follows deterministic, stochastic, or chaotic dynamics. If randomness and chaos are absent from virulence, there is hope for prediction in the future regarding the outcome of microbe-host interactions. Chaotic systems are inherently unpredictable, although it is possible to generate short-term probabilistic models, as is done in applications of stochastic processes and machine learning to weather forecasting. Information on the dynamics of a system is also essential for understanding the reproducibility of experiments, a topic of great concern in the biological sciences. Our study finds preliminary evidence for chaotic dynamics in infectious diseases.


Assuntos
Doenças Transmissíveis , Interações entre Hospedeiro e Microrganismos , Animais , Drosophila melanogaster , Reprodutibilidade dos Testes , Matemática
3.
J Med Genet ; 61(2): 163-170, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-37816627

RESUMO

BACKGROUND: Complex regional pain syndrome type 1 (CRPS-1) is a rare, disabling and sometimes chronic disorder usually arising after a trauma. This exploratory study examined whether patients with chronic CRPS-1 have a different genetic profile compared with those who do not have the condition. METHODS: Exome sequencing was performed to seek altered non-synonymous SNP allele frequencies in a discovery cohort of well-characterised patients with chronic CRPS-1 (n=34) compared with population databases. Identified SNP alleles were confirmed by Sanger sequencing and sought in a replication cohort (n=50). Gene expression of peripheral blood macrophages was assessed. RESULTS: In the discovery cohort, the rare allele frequencies of four non-synonymous SNPs were statistically increased. The replication cohort confirmed this finding. In a chronic pain cohort, these alleles were not overexpressed. In total, 25 out of 84 (29.8%) patients with CRPS-1 expressed a rare allele. The SNPs were rs41289586 in ANO10, rs28360457 in P2RX7, rs1126930 in PRKAG1 and rs80308281 in SLC12A9. Males were more likely than females to have a rare SNP allele, 8 out of 14 (57.1%) vs 17 out of 70 (24.3%) (Fisher's p=0.023). ANO10, P2RX7, PRKAG1 and SLC12A9 were all expressed in macrophages from healthy human controls. CONCLUSION: A single SNP in each of the genes ANO10, P2RX7, PRKAG1 and SLC12A9 was associated with developing chronic CRPS-1, with more males than females expressing these rare alleles. Our work suggests the possibility that a permissive genetic background is an important factor in the development of CRPS-1.


Assuntos
Síndromes da Dor Regional Complexa , Masculino , Feminino , Humanos , Síndromes da Dor Regional Complexa/genética , Síndromes da Dor Regional Complexa/epidemiologia , Frequência do Gene , Polimorfismo de Nucleotídeo Único/genética , Alelos , Patrimônio Genético
4.
Brain ; 147(3): 816-829, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109776

RESUMO

The amygdala was highlighted as an early site for neurofibrillary tau tangle pathology in Alzheimer's disease in the seminal 1991 article by Braak and Braak. This knowledge has, however, only received traction recently with advances in imaging and image analysis techniques. Here, we provide a cross-disciplinary overview of pathology and neuroimaging studies on the amygdala. These studies provide strong support for an early role of the amygdala in Alzheimer's disease and the utility of imaging biomarkers of the amygdala in detecting early changes and predicting decline in cognitive functions and neuropsychiatric symptoms in early stages. We summarize the animal literature on connectivity of the amygdala, demonstrating that amygdala nuclei that show the earliest and strongest accumulation of neurofibrillary tangle pathology are those that are connected to brain regions that also show early neurofibrillary tangle accumulation. Additionally, we propose an alternative pathway of neurofibrillary tangle spreading within the medial temporal lobe between the amygdala and the anterior hippocampus. The proposed existence of this pathway is strengthened by novel experimental data on human functional connectivity. Finally, we summarize the functional roles of the amygdala, highlighting the correspondence between neurofibrillary tangle accumulation and symptomatic profiles in Alzheimer's disease. In summary, these findings provide a new impetus for studying the amygdala in Alzheimer's disease and a unique perspective to guide further study on neurofibrillary tangle spreading and the occurrence of neuropsychiatric symptoms in Alzheimer's disease.


Assuntos
Doença de Alzheimer , Animais , Humanos , Doença de Alzheimer/diagnóstico por imagem , Emaranhados Neurofibrilares , Tonsila do Cerebelo/diagnóstico por imagem , Lobo Temporal , Cognição
5.
Adv Med Educ Pract ; 14: 957-960, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693300

RESUMO

Introduction: Health professions educators are increasingly recognizing the fundamental role the arts and humanities play in professional identity formation; however, few reports exist of programs designed specifically for pre-health professional students. Methods: We designed and delivered four, 2.5-h sessions for pre-health professions students at a local museum in partnership with museum educators. Participants were invited to respond to a follow-up survey asking about their perceived insights from and importance of the session. We used descriptive statistics and thematic content analysis for quantitative and qualitative data, respectively. Results: Ten of the participants responded to the survey (n=10/23, response rate=43%) and all supported the integration of such an experience in their pre-health curriculum. The qualitative analysis of responses to the open-ended item about any insights gained from participation in the program revealed three themes: cultivation of the health professional, personal growth, and awareness and appreciation of multiple perspectives. Discussion: Participants who responded to our survey drew meaningful connections to the relevance of these sessions to their development as future professionals.

6.
bioRxiv ; 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37034802

RESUMO

This paper explicates a solution to the problem of building correspondences between molecular-scale transcriptomics and tissue-scale atlases. The central model represents spatial transcriptomics as generalized functions encoding molecular position and high-dimensional transcriptomic-based (gene, cell type) identity. We map onto low-dimensional atlas ontologies by modeling each atlas compartment as a homogeneous random field with unknown transcriptomic feature distribution. The algorithm presented solves simultaneously for the minimizing geodesic diffeomorphism of coordinates and latent atlas transcriptomic feature fractions by alternating LDDMM optimization for coordinate transformations and quadratic programming for the latent transcriptomic variables. We demonstrate the universality of the algorithm in mapping tissue atlases to gene-based and cell-based MERFISH datasets as well as to other tissue scale atlases. The joint estimation of diffeomorphisms and latent feature distributions allows integration of diverse molecular and cellular datasets into a single coordinate system and creates an avenue of comparison amongst atlas ontologies for continued future development.

7.
Med Educ Online ; 28(1): 2202914, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37074677

RESUMO

PURPOSE: We implemented and evaluated a hybrid 4-week arts-based elective for clinical medical students to support flourishing. MATERIALS AND METHODS: Five students participated in early 2022. Twelve sessions occurred in-person at art museums and other cultural centers, and five occurred online. Sessions incorporated varied arts-based learning activities, including Visual Thinking Strategies, a jazz seminar, and a mask-making workshop. We evaluated the course via weekly reflective essays, interviews 6 weeks after the course, and pre-post surveys that included four scales with clinical relevance: capacity for wonder (CfW), tolerance for ambiguity (TFA), interpersonal reactivity index, and openness to diversity. RESULTS: Qualitatively, the course helped learners: 1) reconnect with individual characteristics and interests that had been neglected during medical education; 2) better appreciate others' perspectives; 3) develop identities as physicians; and 4) engage in quiet reflection, renewing their sense of purpose. Quantitatively, pre-post mean totals increased for the CfW (32.0 [SD 6.8] vs 44.0 [SD 5.7], p=.006) and TFA scales (16.4 [SD 5.2] vs 24.2 [SD 6.9], p=.033). CONCLUSIONS: This elective facilitated learners' connecting with themselves, others, and their profession with improvement in clinically-relevant measures. This provides further evidence that arts-based education can foster professional identity formation and be transformative for students.


Assuntos
Arte , Educação Médica , Estudantes de Medicina , Humanos , Museus , Aprendizagem , Currículo
8.
Neuroimage Clin ; 38: 103374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36934675

RESUMO

Previous research has emphasized the unique impact of Alzheimer's Disease (AD) pathology on the medial temporal lobe (MTL), a reflection that tau pathology is particularly striking in the entorhinal and transentorhinal cortex (ERC, TEC) early in the course of disease. However, other brain regions are affected by AD pathology during its early phases. Here, we use longitudinal diffeomorphometry to measure the atrophy rate from MRI of the amygdala compared with that in the ERC and TEC in cognitively unimpaired (CU) controls, CU individuals who progressed to mild cognitive impairment (MCI), and individuals with MCI who progressed to dementia of the AD type (DAT), using a dataset from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Our results show significantly higher atrophy rates of the amygdala in both groups of 'converters' (CU→MCI, MCI→DAT) compared to controls, with rates of volume loss comparable to rates of thickness loss in the ERC and TEC. We localize atrophy within the amygdala within each of these groups using fixed effects modeling. Controlling for the familywise error rate highlights the medial regions of the amygdala as those with significantly higher atrophy in both groups of converters than in controls. Using our recently developed method, referred to as Projective LDDMM, we map measures of neurofibrillary tau tangles (NFTs) from digital pathology to MRI atlases and reconstruct dense 3D spatial distributions of NFT density within regions of the MTL. The distribution of NFTs is consistent with the spatial distribution of MR measured atrophy rates, revealing high densities (and atrophy) in the amygdala (particularly medial), ERC, and rostral third of the MTL. The similarity of the location of NFTs in AD and shape changes in a well-defined clinical population suggests that amygdalar atrophy rate, as measured through MRI may be a viable biomarker for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Imageamento Tridimensional , Lobo Temporal/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Imageamento por Ressonância Magnética , Atrofia/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia
9.
bioRxiv ; 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36561184

RESUMO

Host-microbe interactions constitute dynamical systems that can be represented by mathematical formulations that determine their dynamic nature, and are categorized as deterministic, stochastic, or chaotic. Knowing the type of dynamical interaction is essential for understanding the system under study. Very little experimental work has been done to determine the dynamical characteristics of host-microbe interactions and its study poses significant challenges. The most straightforward experimental outcome involves an observation of time to death upon infection. However, in measuring this outcome, the internal parameters, and the dynamics of each particular host-microbe interaction in a population of interactions are hidden from the experimentalist. To investigate whether a time-to-death (time to event) dataset provides adequate information for searching for chaotic signatures, we first determined our ability to detect chaos in simulated data sets of time-to-event measurements and successfully distinguished the time-to-event distribution of a chaotic process from a comparable stochastic one. To do so, we introduced an inversion measure to test for a chaotic signature in time-to-event distributions. Next, we searched for chaos, in time-to-death of Caenorhabditis elegans and Drosophila melanogaster infected with Pseudomonas aeruginosa or Pseudomonas entomophila, respectively. We found suggestions of chaotic signatures in both systems, but caution that our results are preliminary and highlight the need for more fine-grained and larger data sets in determining dynamical characteristics. If validated, chaos in host-microbe interactions would have important implications for the occurrence and outcome of infectious diseases, the reproducibility of experiments in the field of microbial pathogenesis and the prediction of microbial threats.

10.
Med Educ Online ; 28(1): 2145105, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36373894

RESUMO

BACKGROUND: Professional identity formation is an important aspect of medical education that can be difficult to translate into formal curricula. The role of arts and humanities programs in fostering professional identity formation remains understudied. Analyzing learners' written reflections, we explore the relationship between an arts-based course and themes of professional identity formation. MATERIALS AND METHODS: Two cohorts of learners participated in a 5-day online course featuring visual arts-based group activities. Both cohorts responded to a prompt with written reflections at the beginning and end of the course. Using a thematic analysis method, we qualitatively analyzed one set of reflections from each cohort. RESULTS: Themes included the nature of the good life; fulfilling, purposeful work; entering the physician role; exploration of emotional experience; and personal growth. Reflections written at the end of the course engaged significantly with art - including literature, poetry, lyrics, and film. One student disclosed a mental illness in their reflection. CONCLUSIONS: Our qualitative analysis of reflections written during a visual arts-based course found several themes related to professional identity formation. Such arts-based courses can also enrich learners' reflections and provide a space for learners to be vulnerable. PRACTICE POINTS: (five short bullets conveying the main points) Arts-based courses can support learners' professional identity formationReflection themes related to professional identity formation included entering the physician role, fulfilling clinical work, and personal growthAt the end of the course, learners' reflections included significant engagement with artReflective writing in small, arts-based learning communities can provide space for learners to be vulnerableThe Role of Arts-Based Curricula in Professional Identity Formation: Results of A Qualitative Analysis of Learner's Written Reflections.


Assuntos
Currículo , Estudantes de Medicina , Humanos , Redação , Ciências Humanas , Aprendizagem , Identificação Social , Estudantes de Medicina/psicologia
11.
Commun Eng ; 12022.
Artigo em Inglês | MEDLINE | ID: mdl-37284027

RESUMO

Reconstructing dense 3D anatomical coordinates from 2D projective measurements has become a central problem in digital pathology for both animal models and human studies. Here we describe Projective Large Deformation Diffeomorphic Metric Mapping (LDDMM), a technique which projects diffeomorphic mappings of dense human magnetic resonance imaging (MRI) atlases at tissue scales onto sparse measurements at micrometre scales associated with histological and more general optical imaging modalities. We solve the problem of dense mapping surjectively onto histological sections by incorporating technologies for crossing modalities that use nonlinear scattering transforms to represent multiple radiomic-like textures at micron scales, together with a Gaussian mixture-model framework for modelling tears and distortions associated to each section. We highlight the significance of our method through incorporation of neuropathological measures and MRI, of relevance to the development of biomarkers for Alzheimer's disease and one instance of the integration of imaging data across the scales of clinical imaging and digital pathology.

12.
JMIR Med Educ ; 7(3): e27923, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34550086

RESUMO

BACKGROUND: The arts and humanities have been integrated into medical student education worldwide. Integrated arts and humanities courses have been found to serve four primary functions: mastering skills, perspective taking, personal insight, and social advocacy. To what extent and how arts and humanities programs achieve these educational outcomes remain unclear. OBJECTIVE: In this study, we aimed to explore how the arts and humanities may lead to perceived benefits in clinical skills development, professional identity formation, and self-care, and to evaluate the feasibility of delivering an arts and humanities-based course online. METHODS: We developed and delivered a 1-week online arts and humanities course to second- through fourth-year medical students. A total of 18 students enrolled in the course across its 2 offerings in Spring 2020. The course was primarily visual arts based but also included activities based in other arts and humanities, such as literature, reflective writing, dance, film, music, philosophy, and religion. Using a mixed methods approach, daily polls assessed student engagement in and perceptions of the various activities, and a postcourse survey assessed student perceptions of the course as a whole. RESULTS: At least 93% of poll respondents (14/15 to 17/18) across the 2 cohorts rated each type of activity as good or excellent. Qualitative analysis of student responses to the postcourse survey revealed themes concerning both the form (overall course design and online format) and the function of the course (skills development, appreciation of new perspectives, and personal inquiry). CONCLUSIONS: Results suggested that the arts and humanities may support the development of clinically relevant skills and attitudes. A more unique finding was that integrative arts and humanities courses delivered online-including those that are primarily visual arts based-engage students and may yield personal and professional benefits.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36283001

RESUMO

Advances in neuroimaging have yielded extensive variety in the scale and type of data available. Effective integration of such data promises deeper understanding of anatomy and disease-with consequences for both diagnosis and treatment. Often catered to particular datatypes or scales, current computational tools and mathematical frameworks remain inadequate for simultaneously registering these multiple modes of "images" and statistically analyzing the ensuing menagerie of data. Here, we present (1) a registration algorithm using a "scattering transform" to align high and low resolution images and (2) a varifold-based modeling framework to compute 3D spatial statistics of multiscale data. We use our methods to quantify microscopic tau pathology across macroscopic 3D regions of the medial temporal lobe to address a major challenge in the diagnosis of Alzheimer's Disease-the reliance on invasive methods to detect microscopic pathology.

14.
Cell Rep ; 32(3): 107941, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32697988

RESUMO

By studying healthy women who do not request analgesia during their first delivery, we investigate genetic effects on labor pain. Such women have normal sensory and psychometric test results, except for significantly higher cuff pressure pain. We find an excess of heterozygotes carrying the rare allele of SNP rs140124801 in KCNG4. The rare variant KV6.4-Met419 has a dominant-negative effect and cannot modulate the voltage dependence of KV2.1 inactivation because it fails to traffic to the plasma membrane. In vivo, Kcng4 (KV6.4) expression occurs in 40% of retrograde-labeled mouse uterine sensory neurons, all of which express KV2.1, and over 90% express the nociceptor genes Trpv1 and Scn10a. In neurons overexpressing KV6.4-Met419, the voltage dependence of inactivation for KV2.1 is more depolarized compared with neurons overexpressing KV6.4. Finally, KV6.4-Met419-overexpressing neurons have a higher action potential threshold. We conclude that KV6.4 can influence human labor pain by modulating the excitability of uterine nociceptors.


Assuntos
Dor do Parto/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Subunidades Proteicas/metabolismo , Adulto , Alelos , Sequência de Aminoácidos , Analgésicos/farmacologia , Animais , Sequência de Bases , Membrana Celular/metabolismo , Cognição , Estudos de Coortes , Emoções , Feminino , Gânglios Espinais/metabolismo , Heterozigoto , Humanos , Ativação do Canal Iônico/genética , Dor do Parto/genética , Dor do Parto/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Mutação/genética , Nociceptores/metabolismo , Limiar da Dor , Polimorfismo de Nucleotídeo Único/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/química , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Gravidez , Multimerização Proteica , Células Receptoras Sensoriais/metabolismo , Canais de Potássio Shab/metabolismo , Frações Subcelulares/metabolismo , Útero/inervação
15.
J Clin Invest ; 130(7): 3805-3819, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298242

RESUMO

Microbial ingestion by a macrophage results in the formation of an acidic phagolysosome but the host cell has no information on the pH susceptibility of the ingested organism. This poses a problem for the macrophage and raises the fundamental question of how the phagocytic cell optimizes the acidification process to prevail. We analyzed the dynamical distribution of phagolysosomal pH in murine and human macrophages that had ingested live or dead Cryptococcus neoformans cells, or inert beads. Phagolysosomal acidification produced a range of pH values that approximated normal distributions, but these differed from normality depending on ingested particle type. Analysis of the increments of pH reduction revealed no forbidden ordinal patterns, implying that the phagosomal acidification process was a stochastic dynamical system. Using simulation modeling, we determined that by stochastically acidifying a phagolysosome to a pH within the observed distribution, macrophages sacrificed a small amount of overall fitness to gain the benefit of reduced variation in fitness. Hence, chance in the final phagosomal pH introduces unpredictability to the outcome of the macrophage-microbe, which implies a bet-hedging strategy that benefits the macrophage. While bet hedging is common in biological systems at the organism level, our results show its use at the organelle and cellular level.


Assuntos
Criptococose/imunologia , Cryptococcus neoformans/imunologia , Macrófagos/imunologia , Fagossomos/imunologia , Animais , Linhagem Celular , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos
16.
MedEdPublish (2016) ; 9: 179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-38073785

RESUMO

This article was migrated. The article was marked as recommended. With the onset of the coronavirus-19 (COVID-19) pandemic, we transformed an in-person art museum-based course for medical students into an online format. This brought new challenges but offered unexpected advantages. The course included daily close-looking of artworks using the Visual Thinking Strategies method, group arts-based activities, reflective writing, and independent creating assignments. The virtual format allowed us to incorporate important features that were unavailable in our in-person elective: multi-media activities, access to nearly unlimited international works of art, and personal reflection from one's private space. As instructors, the experience enlightened us on the value of online arts-based teaching.

17.
J Med Genet ; 55(12): 803-813, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30287594

RESUMO

BACKGROUND: Progressive encephalopathy, hypsarrhythmia and optic atrophy (PEHO) has been described as a clinically distinct syndrome. It has been postulated that it is an autosomal recessive condition. However, the aetiology is poorly understood, and the genetic basis of the condition has not been fully elucidated. Our objective was to discover if PEHO syndrome is a single gene disorder. METHOD: Children with PEHO and PEHO-like syndrome were recruited. Clinical, neurological and dysmorphic features were recorded; EEG reports and MRI scans were reviewed. Where possible, exome sequencing was carried out first to seek mutations in known early infantile developmental and epileptic encephalopathy (DEE) genes and then to use an agnostic approach to seek novel candidate genes. We sought intra-interfamilial phenotypic correlations and genotype-phenotype correlations when pathological mutations were identified. RESULTS: Twenty-three children were recruited from a diverse ethnic background, 19 of which were suitable for inclusion. They were similar in many of the core and the supporting features of PEHO, but there was significant variation in MRI and ophthalmological findings, even between siblings with the same mutation. A pathogenic genetic variant was identified in 15 of the 19 children. One further girl's DNA failed analysis, but her two affected sisters shared confirmed variants. Pathogenic variants were identified in seven different genes. CONCLUSIONS: We found significant clinical and genetic heterogeneity. Given the intrafamily variation demonstrated, we question whether the diagnostic criteria for MRI and ophthalmic findings should be altered. We also question whether PEHO and PEHO-like syndrome represent differing points on a clinical spectrum of the DEE. We conclude that PEHO and PEHO-like syndrome are clinically and genetically diverse entities-and are phenotypic endpoints of many severe genetic encephalopathies.


Assuntos
Edema Encefálico/diagnóstico , Edema Encefálico/etiologia , Epilepsia/diagnóstico , Epilepsia/genética , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/etiologia , Atrofia Óptica/diagnóstico , Atrofia Óptica/etiologia , Espasmos Infantis/diagnóstico , Espasmos Infantis/etiologia , Fatores Etários , Alelos , Biomarcadores , Pré-Escolar , Eletroencefalografia , Fácies , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Genótipo , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Mutação , Linhagem , Fenótipo
18.
BMC Genomics ; 18(1): 944, 2017 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-29202707

RESUMO

BACKGROUND: Significant human diseases/phenotypes exist which require both an environmental trigger event and a genetic predisposition before the disease/phenotype emerges, e.g. Carbamazepine with the rare SNP allele of rs3909184 causing Stevens Johnson syndrome, and aminoglycosides with rs267606617 causing sensory neural deafness. The underlying genotypes are fully penetrant only when the correct environmental trigger(s) occur, otherwise they are silent and harmless. Such diseases/phenotypes will not appear to have a Mendelian inheritance pattern, unless the environmental trigger is very common (>50% per lifetime). The known causative genotypes are likely to be protein-altering SNPs with dominant/semi-dominant effect. We questioned whether other diseases and phenotypes could have a similar aetiology. METHODS: We wrote the fSNPd program to analyse multiple exomes from a test cohort simultaneously with the purpose of identifying SNP alleles at a significantly different frequency to that of the general population. fSNPd was tested on trial cohorts, iteratively improved, and modelled for performance against an idealised association study under mutliple parameters. We also assessed the seqeuncing depath of all human exons to determine which were sufficiently well sequenced in an exome to be sued by fSNPd - by assessing forty exomes base by base. RESULTS: We describe a simple methodology for the detection of SNPs capable of causing a phenotype triggered by an environmental event. This uses cohorts of relatively small size (30-100 individuals) with the phenotype being investigated, their exomes, and thence seeks SNP allele frequencies significantly different from expected to identify potentially clinically important, protein altering SNP alleles. The strengths and weaknesses of this approach for discovering significant genetic causes of human disease are comparable to Mendelian disease mutation detection and Association Studies. CONCLUSIONS: The fSNPd methodology is another approach, and has potentially significant advantage over Association studies in needing far fewer individuals, to detect genes involved in the pathogenesis of a diseases/phenotypes. Furthermore, the SNP alleles identified alter amino acids, potentially making it easier to devise functional assays of protein function to determine pathogenicity.


Assuntos
Interação Gene-Ambiente , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Síndrome de Stevens-Johnson/genética , Síndrome de Stevens-Johnson/patologia , Alelos , Estudos de Coortes , Exoma , Genótipo , Humanos , Fenótipo
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