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1.
Gigascience ; 132024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38837943

RESUMO

Genomic information is increasingly used to inform medical treatments and manage future disease risks. However, any personal and societal gains must be carefully balanced against the risk to individuals contributing their genomic data. Expanding our understanding of actionable genomic insights requires researchers to access large global datasets to capture the complexity of genomic contribution to diseases. Similarly, clinicians need efficient access to a patient's genome as well as population-representative historical records for evidence-based decisions. Both researchers and clinicians hence rely on participants to consent to the use of their genomic data, which in turn requires trust in the professional and ethical handling of this information. Here, we review existing and emerging solutions for secure and effective genomic information management, including storage, encryption, consent, and authorization that are needed to build participant trust. We discuss recent innovations in cloud computing, quantum-computing-proof encryption, and self-sovereign identity. These innovations can augment key developments from within the genomics community, notably GA4GH Passports and the Crypt4GH file container standard. We also explore how decentralized storage as well as the digital consenting process can offer culturally acceptable processes to encourage data contributions from ethnic minorities. We conclude that the individual and their right for self-determination needs to be put at the center of any genomics framework, because only on an individual level can the received benefits be accurately balanced against the risk of exposing private information.


Assuntos
Genômica , Humanos , Genômica/métodos , Genômica/ética , Segurança Computacional , Computação em Nuvem , Consentimento Livre e Esclarecido
2.
Gigascience ; 122023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36994871

RESUMO

BACKGROUND: One difficulty in testing the hypothesis that the Australasian dingo is a functional intermediate between wild wolves and domesticated breed dogs is that there is no reference specimen. Here we link a high-quality de novo long-read chromosomal assembly with epigenetic footprints and morphology to describe the Alpine dingo female named Cooinda. It was critical to establish an Alpine dingo reference because this ecotype occurs throughout coastal eastern Australia where the first drawings and descriptions were completed. FINDINGS: We generated a high-quality chromosome-level reference genome assembly (Canfam_ADS) using a combination of Pacific Bioscience, Oxford Nanopore, 10X Genomics, Bionano, and Hi-C technologies. Compared to the previously published Desert dingo assembly, there are large structural rearrangements on chromosomes 11, 16, 25, and 26. Phylogenetic analyses of chromosomal data from Cooinda the Alpine dingo and 9 previously published de novo canine assemblies show dingoes are monophyletic and basal to domestic dogs. Network analyses show that the mitochondrial DNA genome clusters within the southeastern lineage, as expected for an Alpine dingo. Comparison of regulatory regions identified 2 differentially methylated regions within glucagon receptor GCGR and histone deacetylase HDAC4 genes that are unmethylated in the Alpine dingo genome but hypermethylated in the Desert dingo. Morphologic data, comprising geometric morphometric assessment of cranial morphology, place dingo Cooinda within population-level variation for Alpine dingoes. Magnetic resonance imaging of brain tissue shows she had a larger cranial capacity than a similar-sized domestic dog. CONCLUSIONS: These combined data support the hypothesis that the dingo Cooinda fits the spectrum of genetic and morphologic characteristics typical of the Alpine ecotype. We propose that she be considered the archetype specimen for future research investigating the evolutionary history, morphology, physiology, and ecology of dingoes. The female has been taxidermically prepared and is now at the Australian Museum, Sydney.


Assuntos
Canidae , Genoma Mitocondrial , Lobos , Cães , Animais , Feminino , Epigenoma , Filogenia , Austrália , Canidae/genética , Lobos/genética , Cromossomos
3.
bioRxiv ; 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36747621

RESUMO

Background: One difficulty in testing the hypothesis that the Australasian dingo is a functional intermediate between wild wolves and domesticated breed dogs is that there is no reference specimen. Here we link a high-quality de novo long read chromosomal assembly with epigenetic footprints and morphology to describe the Alpine dingo female named Cooinda. It was critical to establish an Alpine dingo reference because this ecotype occurs throughout coastal eastern Australia where the first drawings and descriptions were completed. Findings: We generated a high-quality chromosome-level reference genome assembly (Canfam_ADS) using a combination of Pacific Bioscience, Oxford Nanopore, 10X Genomics, Bionano, and Hi-C technologies. Compared to the previously published Desert dingo assembly, there are large structural rearrangements on Chromosomes 11, 16, 25 and 26. Phylogenetic analyses of chromosomal data from Cooinda the Alpine dingo and nine previously published de novo canine assemblies show dingoes are monophyletic and basal to domestic dogs. Network analyses show that the mtDNA genome clusters within the southeastern lineage, as expected for an Alpine dingo. Comparison of regulatory regions identified two differentially methylated regions within glucagon receptor GCGR and histone deacetylase HDAC4 genes that are unmethylated in the Alpine dingo genome but hypermethylated in the Desert dingo. Morphological data, comprising geometric morphometric assessment of cranial morphology place dingo Cooinda within population-level variation for Alpine dingoes. Magnetic resonance imaging of brain tissue show she had a larger cranial capacity than a similar-sized domestic dog. Conclusions: These combined data support the hypothesis that the dingo Cooinda fits the spectrum of genetic and morphological characteristics typical of the Alpine ecotype. We propose that she be considered the archetype specimen for future research investigating the evolutionary history, morphology, physiology, and ecology of dingoes. The female has been taxidermically prepared and is now at the Australian Museum, Sydney.

4.
Nature ; 609(7927): 552-559, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045292

RESUMO

Prostate cancer is characterized by considerable geo-ethnic disparity. African ancestry is a significant risk factor, with mortality rates across sub-Saharan Africa of 2.7-fold higher than global averages1. The contributing genetic and non-genetic factors, and associated mutational processes, are unknown2,3. Here, through whole-genome sequencing of treatment-naive prostate cancer samples from 183 ancestrally (African versus European) and globally distinct patients, we generate a large cancer genomics resource for sub-Saharan Africa, identifying around 2 million somatic variants. Significant African-ancestry-specific findings include an elevated tumour mutational burden, increased percentage of genome alteration, a greater number of predicted damaging mutations and a higher total of mutational signatures, and the driver genes NCOA2, STK19, DDX11L1, PCAT1 and SETBP1. Examining all somatic mutational types, we describe a molecular taxonomy for prostate cancer differentiated by ancestry and defined as global mutational subtypes (GMS). By further including Chinese Asian data, we confirm that GMS-B (copy-number gain) and GMS-D (mutationally noisy) are specific to African populations, GMS-A (mutationally quiet) is universal (all ethnicities) and the African-European-restricted subtype GMS-C (copy-number losses) predicts poor clinical outcomes. In addition to the clinical benefit of including individuals of African ancestry, our GMS subtypes reveal different evolutionary trajectories and mutational processes suggesting that both common genetic and environmental factors contribute to the disparity between ethnicities. Analogous to gene-environment interaction-defined here as a different effect of an environmental surrounding in people with different ancestries or vice versa-we anticipate that GMS subtypes act as a proxy for intrinsic and extrinsic mutational processes in cancers, promoting global inclusion in landmark studies.


Assuntos
População Negra , Neoplasias da Próstata , África/etnologia , África Subsaariana/etnologia , Povo Asiático/genética , População Negra/genética , Proteínas de Transporte/genética , China/etnologia , Etnicidade/genética , Europa (Continente)/etnologia , Humanos , Masculino , Mutação , Proteínas Nucleares/genética , Coativador 2 de Receptor Nuclear/genética , Neoplasias da Próstata/genética , RNA Helicases/genética , RNA Longo não Codificante/genética
5.
Genome Med ; 14(1): 100, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045381

RESUMO

BACKGROUND: African ancestry is a significant risk factor for advanced prostate cancer (PCa). Mortality rates in sub-Saharan Africa are 2.5-fold greater than global averages. However, the region has largely been excluded from the benefits of whole genome interrogation studies. Additionally, while structural variation (SV) is highly prevalent, PCa genomic studies are still biased towards small variant interrogation. METHODS: Using whole genome sequencing and best practice workflows, we performed a comprehensive analysis of SVs for 180 (predominantly Gleason score ≥ 8) prostate tumours derived from 115 African, 61 European and four ancestrally admixed patients. We investigated the landscape and relationship of somatic SVs in driving ethnic disparity (African versus European), with a focus on African men from southern Africa. RESULTS: Duplication events showed the greatest ethnic disparity, with a 1.6- (relative frequency) to 2.5-fold (count) increase in African-derived tumours. Furthermore, we found duplication events to be associated with CDK12 inactivation and MYC copy number gain, and deletion events associated with SPOP mutation. Overall, African-derived tumours were 2-fold more likely to present with a hyper-SV subtype. In addition to hyper-duplication and deletion subtypes, we describe a new hyper-translocation subtype. While we confirm a lower TMPRSS2-ERG fusion-positive rate in tumours from African cases (10% versus 33%), novel African-specific PCa ETS family member and TMPRSS2 fusion partners were identified, including LINC01525, FBXO7, GTF3C2, NTNG1 and YPEL5. Notably, we found 74 somatic SV hotspots impacting 18 new candidate driver genes, with CADM2, LSAMP, PTPRD, PDE4D and PACRG having therapeutic implications for African patients. CONCLUSIONS: In this first African-inclusive SV study for high-risk PCa, we demonstrate the power of SV interrogation for the identification of novel subtypes, oncogenic drivers and therapeutic targets. Identifying a novel spectrum of SVs in tumours derived from African patients provides a mechanism that may contribute, at least in part, to the observed ethnic disparity in advanced PCa presentation in men of African ancestry.


Assuntos
Neoplasias da Próstata , População Negra/genética , Carcinogênese/genética , Humanos , Masculino , Mutação , Gradação de Tumores , Proteínas Nucleares/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Repressoras/genética
6.
NPJ Regen Med ; 7(1): 31, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710627

RESUMO

The impact of aging on intestinal stem cells (ISCs) has not been fully elucidated. In this study, we identified widespread epigenetic and transcriptional alterations in old ISCs. Using a reprogramming algorithm, we identified a set of key transcription factors (Egr1, Irf1, FosB) that drives molecular and functional differences between old and young states. Overall, by dissecting the molecular signature of aged ISCs, our study identified transcription factors that enhance the regenerative capacity of ISCs.

7.
Sci Adv ; 8(16): eabm5944, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35452284

RESUMO

Dogs are uniquely associated with human dispersal and bring transformational insight into the domestication process. Dingoes represent an intriguing case within canine evolution being geographically isolated for thousands of years. Here, we present a high-quality de novo assembly of a pure dingo (CanFam_DDS). We identified large chromosomal differences relative to the current dog reference (CanFam3.1) and confirmed no expanded pancreatic amylase gene as found in breed dogs. Phylogenetic analyses using variant pairwise matrices show that the dingo is distinct from five breed dogs with 100% bootstrap support when using Greenland wolf as the outgroup. Functionally, we observe differences in methylation patterns between the dingo and German shepherd dog genomes and differences in serum biochemistry and microbiome makeup. Our results suggest that distinct demographic and environmental conditions have shaped the dingo genome. In contrast, artificial human selection has likely shaped the genomes of domestic breed dogs after divergence from the dingo.


Assuntos
Canidae , Lobos , Animais , Austrália , Cruzamento , Canidae/genética , Cães , Filogenia , Lobos/genética
9.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32379294

RESUMO

Somatic structural variants (SVs), which are variants that typically impact >50 nucleotides, play a significant role in cancer development and evolution but are notoriously more difficult to detect than small variants from short-read next-generation sequencing (NGS) data. This is due to a combination of challenges attributed to the purity of tumour samples, tumour heterogeneity, limitations of short-read information from NGS and sequence alignment ambiguities. In spite of active development of SV detection tools (callers) over the past few years, each method has inherent advantages and limitations. In this review, we highlight some of the important factors affecting somatic SV detection and compared the performance of seven commonly used SV callers. In particular, we focus on the extent of change in sensitivity and precision for detecting different SV types and size ranges from samples with differing variant allele frequencies and sequencing depths of coverage. We highlight the reasons for why some SV callers perform well in some settings but not others, allowing our evaluation findings to be extended beyond the seven SV callers examined in this paper. As the importance of large SVs become increasingly recognized in cancer genomics, this paper provides a timely review on some of the most impactful factors influencing somatic SV detection that should be considered when choosing SV callers.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias/genética , Frequência do Gene , Variação Genética , Humanos , Neoplasias/patologia , Análise de Sequência de DNA/métodos
10.
PLoS One ; 15(8): e0238108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853264

RESUMO

Somatic structural variants are an important contributor to cancer development and evolution. Accurate detection of these complex variants from whole genome sequencing data is influenced by a multitude of parameters. However, there are currently no tools for guiding study design nor are there applications that could predict the performance of somatic structural variant detection. To address this gap, we developed Shiny-SoSV, a user-friendly web-based calculator for determining the impact of common variables on the sensitivity, precision and F1 score of somatic structural variant detection, including choice of variant detection tool, sequencing depth of coverage, variant allele fraction, and variant breakpoint resolution. Using simulation studies, we determined singular and combinatoric effects of these variables, modelled the results using a generalised additive model, allowing structural variant detection performance to be predicted for any combination of predictors. Shiny-SoSV provides an interactive and visual platform for users to easily compare individual and combined impact of different parameters. It predicts the performance of a proposed study design, on somatic structural variant detection, prior to the commencement of benchwork. Shiny-SoSV is freely available at https://hcpcg.shinyapps.io/Shiny-SoSV with accompanying user's guide and example use-cases.


Assuntos
Biologia Computacional/métodos , Variação Genética/genética , Algoritmos , Carcinogênese/genética , Genoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Internet , Neoplasias/genética , Software
11.
Cell Stem Cell ; 27(4): 646-662.e7, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32693086

RESUMO

Epidermal growth factor (EGF) maintains intestinal stem cell (ISC) proliferation and is a key component of organoid growth media yet is dispensable for intestinal homeostasis, suggesting roles for multiple EGF family ligands in ISC function. Here, we identified neuregulin 1 (NRG1) as a key EGF family ligand that drives tissue repair following injury. NRG1, but not EGF, is upregulated upon damage and is expressed in mesenchymal stromal cells, macrophages, and Paneth cells. NRG1 deletion reduces proliferation in intestinal crypts and compromises regeneration capacity. NRG1 robustly stimulates proliferation in crypts and induces budding in organoids, in part through elevated and sustained activation of mitogen-activated protein kinase (MAPK) and AKT. Consistently, NRG1 treatment induces a proliferative gene signature and promotes organoid formation from progenitor cells and enhances regeneration following injury. These data suggest mesenchymal-derived NRG1 is a potent mediator of tissue regeneration and may inform the development of therapies for enhancing intestinal repair after injury.


Assuntos
Intestinos , Neuregulina-1 , Proliferação de Células , Epitélio , Celulas de Paneth
12.
Cancers (Basel) ; 12(5)2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32392735

RESUMO

BACKGROUND: While critical insights have been gained from evaluating the genomic landscape of metastatic prostate cancer, utilizing this information to inform personalized treatment is in its infancy. We performed a retrospective pilot study to assess the current impact of precision medicine for locally advanced and metastatic prostate adenocarcinoma and evaluate how genomic data could be harnessed to individualize treatment. METHODS: Deep whole genome-sequencing was performed on 16 tumour-blood pairs from 13 prostate cancer patients; whole genome optical mapping was performed in a subset of 9 patients to further identify large structural variants. Tumour samples were derived from prostate, lymph nodes, bone and brain. RESULTS: Most samples had acquired genomic alterations in multiple therapeutically relevant pathways, including DNA damage response (11/13 cases), PI3K (7/13), MAPK (10/13) and Wnt (9/13). Five patients had somatic copy number losses in genes that may indicate sensitivity to immunotherapy (LRP1B, CDK12, MLH1) and one patient had germline and somatic BRCA2 alterations. CONCLUSIONS: Most cases, whether primary or metastatic, harboured therapeutically relevant alterations, including those associated with PARP inhibitor sensitivity, immunotherapy sensitivity and resistance to androgen pathway targeting agents. The observed intra-patient heterogeneity and presence of genomic alterations in multiple growth pathways in individual cases suggests that a precision medicine model in prostate cancer needs to simultaneously incorporate multiple pathway-targeting agents. Our whole genome approach allowed for structural variant assessment in addition to the ability to rapidly reassess an individual's molecular landscape as knowledge of relevant biomarkers evolve. This retrospective oncological assessment highlights the genomic complexity of prostate cancer and the potential impact of assessing genomic data for an individual at any stage of the disease.

13.
Gigascience ; 9(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236524

RESUMO

BACKGROUND: The German Shepherd Dog (GSD) is one of the most common breeds on earth and has been bred for its utility and intelligence. It is often first choice for police and military work, as well as protection, disability assistance, and search-and-rescue. Yet, GSDs are well known to be susceptible to a range of genetic diseases that can interfere with their training. Such diseases are of particular concern when they occur later in life, and fully trained animals are not able to continue their duties. FINDINGS: Here, we provide the draft genome sequence of a healthy German Shepherd female as a reference for future disease and evolutionary studies. We generated this improved canid reference genome (CanFam_GSD) utilizing a combination of Pacific Bioscience, Oxford Nanopore, 10X Genomics, Bionano, and Hi-C technologies. The GSD assembly is ∼80 times as contiguous as the current canid reference genome (20.9 vs 0.267 Mb contig N50), containing far fewer gaps (306 vs 23,876) and fewer scaffolds (429 vs 3,310) than the current canid reference genome CanFamv3.1. Two chromosomes (4 and 35) are assembled into single scaffolds with no gaps. BUSCO analyses of the genome assembly results show that 93.0% of the conserved single-copy genes are complete in the GSD assembly compared with 92.2% for CanFam v3.1. Homology-based gene annotation increases this value to ∼99%. Detailed examination of the evolutionarily important pancreatic amylase region reveals that there are most likely 7 copies of the gene, indicative of a duplication of 4 ancestral copies and the disruption of 1 copy. CONCLUSIONS: GSD genome assembly and annotation were produced with major improvement in completeness, continuity, and quality over the existing canid reference. This resource will enable further research related to canine diseases, the evolutionary relationships of canids, and other aspects of canid biology.


Assuntos
Cromossomos/genética , Genoma/genética , Análise de Sequência de DNA/métodos , Sequenciamento Completo do Genoma/métodos , Animais , Cães , Genômica , Anotação de Sequência Molecular
14.
Methods Mol Biol ; 2129: 359-383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32056190

RESUMO

While surgery plays a major role in the treatment and potential cure of esophageal cancers, esophagectomy remains a high-risk operation with significant perioperative morbidity and mortality compared to other oncosurgical procedures. Perioperative management for esophagectomy is complex, and close attention to detail in various areas of anesthetic and perioperative management is crucial to improve postoperative outcomes. Patients undergoing esophagectomy should be offered an evidence-based risk assessment for their postoperative outcomes to allow active participation and informed, shared-decision making. Novel perioperative risk scores have been developed to predict both short-term and long-term outcomes in patients with esophageal cancer, although independent validation of such scoring systems is still required. Apart from accurate preoperative risk assessment, further efforts to improve morbidity and mortality from esophagectomy is achieved through comprehensive Enhanced Recovery after Surgery (ERAS) protocols, which comprise an individualized bundle of care throughout the perioperative journey for each patient and should be implemented as a standard practice. Furthermore, anesthetic practice and perioperative anesthetic drug usage can potentially affect cancer progression and recurrence. This chapter reviews current evidence for various factors that contribute to the improvement of perioperative outcomes, including prehabilitation, preoperative optimization of anemia, thoracic epidural analgesia, intraoperative protective ventilatory strategies, goal-directed fluid therapy, as well as special attention to other perioperative issues that potentially reduce anastomotic and cardiopulmonary complications. In summary, it is difficult to show a measurable benefit from any one single intervention, and a multidisciplinary approach that encompasses multiple aspects of perioperative care is necessary to improve outcomes after esophagectomy.


Assuntos
Anestesia/métodos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Esofagectomia/métodos , Adenocarcinoma/patologia , Anestésicos/uso terapêutico , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Esofagectomia/efeitos adversos , Esôfago/patologia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Neoplasias Bucais/patologia , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/etiologia , Fatores de Risco
15.
ACS Macro Lett ; 9(11): 1617-1624, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35617063

RESUMO

We report the first simulations of nonsolvent-induced phase separation (NIPS) that predict membrane microstructures with graded asymmetric pore size distribution. In NIPS, a polymer solution film is immersed in a nonsolvent bath, enriching the film in nonsolvent, and leading to phase separation that forms a solid polymer-rich membrane matrix and polymer-poor membrane pores. We demonstrate how mass-transfer-induced spinodal decomposition, thermal fluctuations, and glass-transition dynamics-implemented with mobility contrast between the polymer-rich and polymer-poor phases-are essential to the formation of asymmetric membrane microstructures. Specifically, we show that the competition between the propagation of the phase-separation and glass-transition fronts determines the degree of pore-size asymmetry. We also explore the sensitivity of these microstructures to the initial film composition, and compare their formation in 2D and 3D.

16.
Nature ; 575(7781): 185-189, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659339

RESUMO

Anatomically modern humans originated in Africa around 200 thousand years ago (ka)1-4. Although some of the oldest skeletal remains suggest an eastern African origin2, southern Africa is home to contemporary populations that represent the earliest branch of human genetic phylogeny5,6. Here we generate, to our knowledge, the largest resource for the poorly represented and deepest-rooting maternal L0 mitochondrial DNA branch (198 new mitogenomes for a total of 1,217 mitogenomes) from contemporary southern Africans and show the geographical isolation of L0d1'2, L0k and L0g KhoeSan descendants south of the Zambezi river in Africa. By establishing mitogenomic timelines, frequencies and dispersals, we show that the L0 lineage emerged within the residual Makgadikgadi-Okavango palaeo-wetland of southern Africa7, approximately 200 ka (95% confidence interval, 240-165 ka). Genetic divergence points to a sustained 70,000-year-long existence of the L0 lineage before an out-of-homeland northeast-southwest dispersal between 130 and 110 ka. Palaeo-climate proxy and model data suggest that increased humidity opened green corridors, first to the northeast then to the southwest. Subsequent drying of the homeland corresponds to a sustained effective population size (L0k), whereas wet-dry cycles and probable adaptation to marine foraging allowed the southwestern migrants to achieve population growth (L0d1'2), as supported by extensive south-coastal archaeological evidence8-10. Taken together, we propose a southern African origin of anatomically modern humans with sustained homeland occupation before the first migrations of people that appear to have been driven by regional climate changes.


Assuntos
População Negra , Migração Humana/história , Filogenia , Áreas Alagadas , População Negra/genética , População Negra/história , Clima , DNA Mitocondrial , Genoma Mitocondrial/genética , Haplótipos , História Antiga , Humanos , Densidade Demográfica , Chuva , Estações do Ano , África do Sul
17.
BMC Med Genomics ; 12(1): 82, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164124

RESUMO

BACKGROUNDS: Genetic diversity is greatest within Africa, in particular the KhoeSan click-speaking peoples of southern Africa. South African populations represent admixture fractions including differing degrees of African, African-KhoeSan and non-African genetic ancestries. Within the United States, African ancestry has been linked to prostate cancer presentation and mortality. Together with environmental contributions, genetics is a significant risk factor for high-risk prostate cancer, defined by a pathological Gleason score ≥ 8. METHODS: Using genotype array data merged with ancestry informative reference data, we investigate the contribution of African ancestral fractions to high-risk prostate cancer. Our study includes 152 South African men of African (Black) or African-admixed (Coloured) ancestries, in which 40% showed high-risk prostate cancer. RESULTS: Genetic fractions were determined for averaging an equal African to non-African genetic ancestral contribution in the Coloured; we found African ancestry to be linked to high-risk prostate cancer (P-value = 0.0477). Adjusting for age, the associated African ancestral fraction was driven by a significant KhoeSan over Bantu contribution, defined by Gleason score ≥ 8 (P-value = 0.02329) or prostate specific antigen levels ≥20 ng/ml (P-value = 0.03713). Additionally, we observed the mean overall KhoeSan contribution to be increased in Black patients with high-risk (11.8%) over low-risk (10.9%) disease. Linking for the first time KhoeSan ancestry to a common modern disease, namely high-risk prostate cancer, we tested in this small study the validity of using KhoeSan ancestry as a surrogate for identifying potential high-risk prostate cancer risk loci. As such, we identified four loci within chromosomal regions 2p11.2, 3p14, 8q23 and 22q13.2 (P-value = all age-adjusted < 0.01), two of which have previously been associated with high-risk prostate cancer. CONCLUSIONS: Our study suggests that ancient KhoeSan ancestry may be linked to common modern diseases, specifically those of late onset and therefore unlikely to have undergone exclusive selective pressure. As such we show within a uniquely admixed South African population a link between KhoeSan ancestry and high-risk prostate cancer, which may explain the 2-fold increase in presentation in Black South Africans compared with African Americans.


Assuntos
População Negra/genética , Predisposição Genética para Doença/genética , Variação Genética , Neoplasias da Próstata/genética , Loci Gênicos/genética , Técnicas de Genotipagem , Humanos , Masculino , Gradação de Tumores , Neoplasias da Próstata/patologia
18.
J Clin Densitom ; 22(1): 52-58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29111198

RESUMO

This study aims to quantitatively evaluate the cumulative effective dose and associated cancer risk of pediatric patients of US and Hong Kong population undergoing repetitive whole-body scans with dual-energy X-ray absorptiometry (DXA) during their diagnosis and follow-up periods. Organ-absorbed doses of pediatric patients undergoing DXA whole-body scan have been computer simulated using patient imaging parameters input to the Monte Carlo software PCXMC. Gender- and age-specific effective doses have been calculated with the simulated organ-absorbed doses using the ICRP-103 approach. The associated radiation-induced cancer risk, expressed as lifetime attributable cancer risk (LAR), has been estimated according to the method introduced in the Biological Effects of Ionizing Radiation VII report. Mathematical fitting for effective dose and for LAR, as a function of age at exposure, has been analytically obtained to quantitatively estimate the cumulated effective dose and LAR for pediatric patients of US and Hong Kong population with repetitive DXA whole-body scan during their follow-up period. The effective dose of a single DXA whole-body scan for patients exposed at the age between 5 and 18 years was calculated as 8.47-17.68 µSv. The corresponding LAR for US and Hong Kong population was between the range of 4.57 × 10-7 and 7.14 × 10-7. The cumulative effective dose of DXA whole-body scan for patients exposed annually at age between 5 and 18 years was calculated as 180 µSv for girls and 168 µSv for boys. The corresponding cumulative LAR for US and Hong Kong population was calculated as 3.77 × 10-6 to 5.48 × 10-6. Girls would be at a statistically significant higher cumulated cancer risk than boys under the same whole-body DXA protocol (p = 0.03). The probability of cumulative LAR for pediatric populations undergoing annual DXA whole-body scan is regarded as minimal. We demonstrate the use of computer simulation and analytic formulation to quantitatively obtain the cumulated effective dose and cancer risk at any age of exposure, which are useful information for medical personnel to track patient radiation dose and to alleviate patients' parents concern about radiation safety in repetitive whole-body scan using DXA.


Assuntos
Absorciometria de Fóton , Neoplasias Induzidas por Radiação/epidemiologia , Doses de Radiação , Irradiação Corporal Total , Adolescente , Criança , Pré-Escolar , Simulação por Computador , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Método de Monte Carlo , Medição de Risco , Estados Unidos/epidemiologia
19.
Front Psychol ; 10: 2899, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038350

RESUMO

This study aimed to investigate the learning effectiveness of reading picture books with EMPATHICS elements using dialogic reading techniques in enhancing young children's English language learning and creativity. EMPATHICS is an acronym of Emotion and Empathy, Meaning and Motivation, Perseverance, Agency and Autonomy, Time, Habits of Mind, Intelligences, Character Strengths, and Self Factors (Oxford, 2016). It adopted a quasi-experimental design, and 78 kindergarten children aged from 4 to 5 years old in a cluster group were randomly assigned to the experimental and control groups. Both groups read the same four picture books with their homeroom teachers, including two readers suggested in the curriculum and two picture books with enriched elements for 12 sessions over 8 weeks. A doubly multivariate analysis was used to measure the main time and group effects and the interaction effect on the performance of English receptive vocabulary, syntactic complexity, and verbal creativity of the two groups across three different times. There were significant differences only in the interactive effect on syntactic complexity. Children in the experimental condition gave responses with more complex syntactic structures. Significant time effects for receptive vocabulary, syntactic complexity, and verbal creativity were observed in all children. Reading enriched English texts better prepares children to creatively and effectively express themselves. This study extends previous research in two ways. First, this study is one of the few studies on the effectiveness of dialogic reading using EMPATHICS-enriched picture books among young language learners. Second, this study investigates the effects of dialogic teaching on English as a second language development in young children. The educational implications will be discussed.

20.
Cancer Res ; 78(24): 6736-6746, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30217929

RESUMO

: African-American men are more likely than any other racial group to die from prostate cancer. The contribution of acquired genomic variation to this racial disparity is largely unknown, as genomic from Africa is lacking. Here, we performed the first tumor-normal paired deep whole-genome sequencing for Africa. A direct study-matched comparison between African- and European-derived, treatment-naïve, high-risk prostate tumors for 15 cases allowed for further comparative analyses of existing data. Excluding a single hypermutated tumor with 55 mutations per megabase, we observed a 1.8-fold increase in small somatic variants in African- versus European-derived tumors (P = 1.02e-04), rising to 4-fold when compared with published tumor-matched data. Furthermore, we observed an increase in oncogenic driver mutations in African tumors (P = 2.92e-03); roughly 30% of impacted genes were novel to prostate cancer, and 79% of recurrent driver mutations appeared early in tumorigenesis. Although complex genomic rearrangements were less frequent in African tumors, we describe a uniquely hyperduplicated tumor affecting 149 transposable elements. Comparable with African Americans, ERG fusions and PIK3CA mutations were absent and PTEN loss less frequent. CCND1 and MYC were frequently gained, with somatic copy-number changes more likely to occur late in tumorigenesis. In addition to traditional prostate cancer gene pathways, genes regulating calcium ion-ATPase signal transduction were disrupted in African tumors. Although preliminary, our results suggest that further validation and investigation into the potential implications for elevated tumor mutational burden and tumor-initiating mutations in clinically unfavorable prostate cancer can improve patient outcomes in Africa. SIGNIFICANCE: The first whole-genome sequencing study for high-risk prostate cancer in African men allows a simultaneous comparison of ethnic differences relative to European populations and of the influences of the environment relative to African-American men. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/78/24/6736/F1.large.jpg.See related commentary by Huang, p. 6726.


Assuntos
Análise Mutacional de DNA , Genoma Humano , Mutação , Neoplasias da Próstata/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , População Negra , Carcinogênese , Europa (Continente) , Frequência do Gene , Rearranjo Gênico , Mutação em Linhagem Germinativa , Disparidades nos Níveis de Saúde , Humanos , Masculino , Família Multigênica , Mutação de Sentido Incorreto , Metástase Neoplásica , Filogenia , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/etnologia , África do Sul , População Branca , Sequenciamento Completo do Genoma
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