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1.
Cell ; 184(10): 2633-2648.e19, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33864768

RESUMO

Long non-coding RNA (lncRNA) genes have well-established and important impacts on molecular and cellular functions. However, among the thousands of lncRNA genes, it is still a major challenge to identify the subset with disease or trait relevance. To systematically characterize these lncRNA genes, we used Genotype Tissue Expression (GTEx) project v8 genetic and multi-tissue transcriptomic data to profile the expression, genetic regulation, cellular contexts, and trait associations of 14,100 lncRNA genes across 49 tissues for 101 distinct complex genetic traits. Using these approaches, we identified 1,432 lncRNA gene-trait associations, 800 of which were not explained by stronger effects of neighboring protein-coding genes. This included associations between lncRNA quantitative trait loci and inflammatory bowel disease, type 1 and type 2 diabetes, and coronary artery disease, as well as rare variant associations to body mass index.


Assuntos
Doença/genética , Herança Multifatorial/genética , População/genética , RNA Longo não Codificante/genética , Transcriptoma , Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Perfilação da Expressão Gênica , Variação Genética , Humanos , Doenças Inflamatórias Intestinais/genética , Especificidade de Órgãos/genética , Locos de Características Quantitativas
2.
Cell ; 179(3): 729-735.e10, 2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31495572

RESUMO

We report an ancient genome from the Indus Valley Civilization (IVC). The individual we sequenced fits as a mixture of people related to ancient Iranians (the largest component) and Southeast Asian hunter-gatherers, a unique profile that matches ancient DNA from 11 genetic outliers from sites in Iran and Turkmenistan in cultural communication with the IVC. These individuals had little if any Steppe pastoralist-derived ancestry, showing that it was not ubiquitous in northwest South Asia during the IVC as it is today. The Iranian-related ancestry in the IVC derives from a lineage leading to early Iranian farmers, herders, and hunter-gatherers before their ancestors separated, contradicting the hypothesis that the shared ancestry between early Iranians and South Asians reflects a large-scale spread of western Iranian farmers east. Instead, sampled ancient genomes from the Iranian plateau and IVC descend from different groups of hunter-gatherers who began farming without being connected by substantial movement of people.


Assuntos
DNA Antigo/química , Genoma Humano , Migração Humana , Linhagem , População/genética , Povo Asiático/genética , Evolução Molecular , Humanos , Irã (Geográfico) , Paquistão
3.
Nucleic Acids Res ; 52(D1): D622-D632, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37930845

RESUMO

Modern medicine is increasingly focused on personalized medicine, and multi-omics data is crucial in understanding biological phenomena and disease mechanisms. Each ethnic group has its unique genetic background with specific genomic variations influencing disease risk and drug response. Therefore, multi-omics data from specific ethnic populations are essential for the effective implementation of personalized medicine. Various prospective cohort studies, such as the UK Biobank, All of Us and Lifelines, have been conducted worldwide. The Tohoku Medical Megabank project was initiated after the Great East Japan Earthquake in 2011. It collects biological specimens and conducts genome and omics analyses to build a basis for personalized medicine. Summary statistical data from these analyses are available in the jMorp web database (https://jmorp.megabank.tohoku.ac.jp), which provides a multidimensional approach to the diversity of the Japanese population. jMorp was launched in 2015 as a public database for plasma metabolome and proteome analyses and has been continuously updated. The current update will significantly expand the scale of the data (metabolome, genome, transcriptome, and metagenome). In addition, the user interface and backend server implementations were rewritten to improve the connectivity between the items stored in jMorp. This paper provides an overview of the new version of the jMorp.


Assuntos
Bases de Dados Genéticas , Multiômica , População , Medicina de Precisão , Humanos , Genômica/métodos , Japão , Estudos Prospectivos , População/genética
4.
Proc Natl Acad Sci U S A ; 119(25): e2119281119, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35696575

RESUMO

Haplotype-based analyses have recently been leveraged to interrogate the fine-scale structure in specific geographic regions, notably in Europe, although an equivalent haplotype-based understanding across the whole of Europe with these tools is lacking. Furthermore, study of identity-by-descent (IBD) sharing in a large sample of haplotypes across Europe would allow a direct comparison between different demographic histories of different regions. The UK Biobank (UKBB) is a population-scale dataset of genotype and phenotype data collected from the United Kingdom, with established sampling of worldwide ancestries. The exact content of these non-UK ancestries is largely uncharacterized, where study could highlight valuable intracontinental ancestry references with deep phenotyping within the UKBB. In this context, we sought to investigate the sample of European ancestry captured in the UKBB. We studied the haplotypes of 5,500 UKBB individuals with a European birthplace; investigated the population structure and demographic history in Europe, showing in parallel the variety of footprints of demographic history in different genetic regions around Europe; and expand knowledge of the genetic landscape of the east and southeast of Europe. Providing an updated map of European genetics, we leverage IBD-segment sharing to explore the extent of population isolation and size across the continent. In addition to building and expanding upon previous knowledge in Europe, our results show the UKBB as a source of diverse ancestries beyond Britain. These worldwide ancestries sampled in the UKBB may complement and inform researchers interested in specific communities or regions not limited to Britain.


Assuntos
Haplótipos , População , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Demografia , Europa (Continente) , Variação Genética , População/genética
5.
PLoS Genet ; 17(2): e1009303, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33539374

RESUMO

Generative models have shown breakthroughs in a wide spectrum of domains due to recent advancements in machine learning algorithms and increased computational power. Despite these impressive achievements, the ability of generative models to create realistic synthetic data is still under-exploited in genetics and absent from population genetics. Yet a known limitation in the field is the reduced access to many genetic databases due to concerns about violations of individual privacy, although they would provide a rich resource for data mining and integration towards advancing genetic studies. In this study, we demonstrated that deep generative adversarial networks (GANs) and restricted Boltzmann machines (RBMs) can be trained to learn the complex distributions of real genomic datasets and generate novel high-quality artificial genomes (AGs) with none to little privacy loss. We show that our generated AGs replicate characteristics of the source dataset such as allele frequencies, linkage disequilibrium, pairwise haplotype distances and population structure. Moreover, they can also inherit complex features such as signals of selection. To illustrate the promising outcomes of our method, we showed that imputation quality for low frequency alleles can be improved by data augmentation to reference panels with AGs and that the RBM latent space provides a relevant encoding of the data, hence allowing further exploration of the reference dataset and features for solving supervised tasks. Generative models and AGs have the potential to become valuable assets in genetic studies by providing a rich yet compact representation of existing genomes and high-quality, easy-access and anonymous alternatives for private databases.


Assuntos
Simulação por Computador , Genoma Humano , Aprendizado de Máquina , População/genética , Algoritmos , Alelos , Cromossomos Humanos Par 15/genética , Bases de Dados Factuais , Bases de Dados Genéticas , Aprendizado Profundo , Projeto HapMap , Humanos , Cadeias de Markov , Redes Neurais de Computação , Polimorfismo de Nucleotídeo Único
6.
Nucleic Acids Res ; 49(8): 4308-4324, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33849068

RESUMO

Variable Number Tandem Repeats (VNTRs) are tandem repeat (TR) loci that vary in copy number across a population. Using our program, VNTRseek, we analyzed human whole genome sequencing datasets from 2770 individuals in order to detect minisatellite VNTRs, i.e., those with pattern sizes ≥7 bp. We detected 35 638 VNTR loci and classified 5676 as commonly polymorphic (i.e. with non-reference alleles occurring in >5% of the population). Commonly polymorphic VNTR loci were found to be enriched in genomic regions with regulatory function, i.e. transcription start sites and enhancers. Investigation of the commonly polymorphic VNTRs in the context of population ancestry revealed that 1096 loci contained population-specific alleles and that those could be used to classify individuals into super-populations with near-perfect accuracy. Search for quantitative trait loci (eQTLs), among the VNTRs proximal to genes, indicated that in 187 genes expression differences correlated with VNTR genotype. We validated our predictions in several ways, including experimentally, through the identification of predicted alleles in long reads, and by comparisons showing consistency between sequencing platforms. This study is the most comprehensive analysis of minisatellite VNTRs in the human population to date.


Assuntos
Regulação da Expressão Gênica , Genoma Humano , Repetições Minissatélites , Polimorfismo Genético , Alelos , Conjuntos de Dados como Assunto , Elementos Facilitadores Genéticos , Humanos , População/genética , Sítio de Iniciação de Transcrição , Sequenciamento Completo do Genoma
7.
PLoS Genet ; 16(8): e1008895, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760067

RESUMO

The sequencing of Neanderthal and Denisovan genomes has yielded many new insights about interbreeding events between extinct hominins and the ancestors of modern humans. While much attention has been paid to the relatively recent gene flow from Neanderthals and Denisovans into modern humans, other instances of introgression leave more subtle genomic evidence and have received less attention. Here, we present a major extension of the ARGweaver algorithm, called ARGweaver-D, which can infer local genetic relationships under a user-defined demographic model that includes population splits and migration events. This Bayesian algorithm probabilistically samples ancestral recombination graphs (ARGs) that specify not only tree topologies and branch lengths along the genome, but also indicate migrant lineages. The sampled ARGs can therefore be parsed to produce probabilities of introgression along the genome. We show that this method is well powered to detect the archaic migration into modern humans, even with only a few samples. We then show that the method can also detect introgressed regions stemming from older migration events, or from unsampled populations. We apply it to human, Neanderthal, and Denisovan genomes, looking for signatures of older proposed migration events, including ancient humans into Neanderthal, and unknown archaic hominins into Denisovans. We identify 3% of the Neanderthal genome that is putatively introgressed from ancient humans, and estimate that the gene flow occurred between 200-300kya. We find no convincing evidence that negative selection acted against these regions. Finally, we predict that 1% of the Denisovan genome was introgressed from an unsequenced, but highly diverged, archaic hominin ancestor. About 15% of these "super-archaic" regions-comprising at least about 4Mb-were, in turn, introgressed into modern humans and continue to exist in the genomes of people alive today.


Assuntos
Fluxo Gênico , Modelos Genéticos , Homem de Neandertal/genética , População/genética , Recombinação Genética , Animais , Evolução Molecular , Migração Humana , Humanos
8.
PLoS Genet ; 16(1): e1008347, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31986135

RESUMO

Detailed comprehensive knowledge of the structures of individual long-range telomere-terminal haplotypes are needed to understand their impact on telomere function, and to delineate the population structure and evolution of subtelomere regions. However, the abundance of large evolutionarily recent segmental duplications and high levels of large structural variations have complicated both the mapping and sequence characterization of human subtelomere regions. Here, we use high throughput optical mapping of large single DNA molecules in nanochannel arrays for 154 human genomes from 26 populations to present a comprehensive look at human subtelomere structure and variation. The results catalog many novel long-range subtelomere haplotypes and determine the frequencies and contexts of specific subtelomeric duplicons on each chromosome arm, helping to clarify the currently ambiguous nature of many specific subtelomere structures as represented in the current reference sequence (HG38). The organization and content of some duplicons in subtelomeres appear to show both chromosome arm and population-specific trends. Based upon these trends we estimate a timeline for the spread of these duplication blocks.


Assuntos
Genoma Humano , População/genética , Telômero/genética , Evolução Molecular , Haplótipos , Humanos , Sequenciamento por Nanoporos/métodos
9.
Proc Natl Acad Sci U S A ; 117(23): 12791-12798, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32457149

RESUMO

Genomic studies conducted on ancient individuals across Europe have revealed how migrations have contributed to its present genetic landscape, but the territory of present-day France has yet to be connected to the broader European picture. We generated a large dataset comprising the complete mitochondrial genomes, Y-chromosome markers, and genotypes of a number of nuclear loci of interest of 243 individuals sampled across present-day France over a period spanning 7,000 y, complemented with a partially overlapping dataset of 58 low-coverage genomes. This panel provides a high-resolution transect of the dynamics of maternal and paternal lineages in France as well as of autosomal genotypes. Parental lineages and genomic data both revealed demographic patterns in France for the Neolithic and Bronze Age transitions consistent with neighboring regions, first with a migration wave of Anatolian farmers followed by varying degrees of admixture with autochthonous hunter-gatherers, and then substantial gene flow from individuals deriving part of their ancestry from the Pontic steppe at the onset of the Bronze Age. Our data have also highlighted the persistence of Magdalenian-associated ancestry in hunter-gatherer populations outside of Spain and thus provide arguments for an expansion of these populations at the end of the Paleolithic Period more northerly than what has been described so far. Finally, no major demographic changes were detected during the transition between the Bronze and Iron Ages.


Assuntos
DNA Antigo , Evolução Molecular , Genoma Humano , Migração Humana , População/genética , Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Feminino , França , Fluxo Gênico , Humanos , Masculino , Polimorfismo Genético
10.
Hum Mol Genet ; 28(R2): R170-R179, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31647093

RESUMO

Mendelian randomization (MR) is increasingly used to make causal inferences in a wide range of fields, from drug development to etiologic studies. Causal inference in MR is possible because of the process of genetic inheritance from parents to offspring. Specifically, at gamete formation and conception, meiosis ensures random allocation to the offspring of one allele from each parent at each locus, and these are unrelated to most of the other inherited genetic variants. To date, most MR studies have used data from unrelated individuals. These studies assume that genotypes are independent of the environment across a sample of unrelated individuals, conditional on covariates. Here we describe potential sources of bias, such as transmission ratio distortion, selection bias, population stratification, dynastic effects and assortative mating that can induce spurious or biased SNP-phenotype associations. We explain how studies of related individuals such as sibling pairs or parent-offspring trios can be used to overcome some of these sources of bias, to provide potentially more reliable evidence regarding causal processes. The increasing availability of data from related individuals in large cohort studies presents an opportunity to both overcome some of these biases and also to evaluate familial environmental effects.


Assuntos
Análise da Randomização Mendeliana , População/genética , Reprodução/genética , Família , Características da Família , Estudos de Associação Genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Viés de Seleção , Sociobiologia/educação
12.
Biochem Genet ; 58(1): 157-170, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31410625

RESUMO

Amphipods of the superfamily Lysianassoidea that inhabit the hadal zone ( > 6000 m) have large bathymetric ranges and play a key role in deep ocean ecosystems. The endemism of these amphipod species makes them a good model for investigating potent natural selection and restricted dispersal in deep ocean trenches. Here, we describe genetic diversity and intraspecific population differentiation among three amphipod species from four Pacific trenches based on a mtDNA concatenated dataset (CO Ι and 16S rRNA genes) from 150 amphipod individuals. All amphipod populations had low genetic diversity, as indicated by haplotype and nucleotide diversity values. Population geographic relationship analysis of two Alicella gigantea populations revealed no genetic differentiation between these two localities (pairwise genetic differentiation coefficient = 0.00032, gene flow = 784.58), and the major variation (99.97%) was derived from variation within the populations. Historical demographic events were investigated using Tajima's D and Fu's F neutrality tests and analysis of mismatch distribution. Consistent results provided strong evidence to support the premise that demographic expansion occurred only for the Mariana population of Hirondellea gigas, possibly within the last 2.1-3.4 million years. These findings suggest that the formation of amphipod population structure might be the result of multiple factors including high hydrostatic pressure, food distribution, trench topographic forcing and potential ecological interactions.


Assuntos
Anfípodes/classificação , Anfípodes/genética , DNA Mitocondrial/genética , Variação Genética/genética , RNA Ribossômico 16S/genética , Animais , Ecossistema , Fluxo Gênico , Oceano Pacífico , População/genética
13.
Molecules ; 26(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375725

RESUMO

The genus Aldrovanda is a Palaeogene element containing a single extant species, Aldrovanda vesiculosa L. This aquatic carnivorous herb has a very wide range of distribution, natively covering four continents; however, it is a critically endangered aquatic plant species worldwide. Previous studies revealed that A. vesiculosa had an extremely low genetic variation. The main aim of the present paper is to explore, using chemometric tools, the diversity of 16 A. vesiculosa populations from various sites from four continents (Eurasia, Africa, Australia). Using chemometric data as markers for genetic diversity, we show the relationships of 16 A. vesiculosa populations from various sites, including four continents. Phytochemical markers allowed the identification of five well-supported (bootstrap > 90%) groups among the 16 populations sampled. The principal component analysis data support the idea that the strongly related African (Botswana) and Australian (Kimberley, NT, NW Australia) populations are the most distant ones, separated from the European and Asian ones. However, considering the five Australian populations sampled, three are nested within the Eurasian group. The chemometric data are correlated positively with the geographical distances between the samples, which suggests a tendency toward isolation for the most distant populations.


Assuntos
Droseraceae/genética , Variação Genética/genética , População/genética , África , Austrália , Droseraceae/química , Modelos Biológicos , Filogenia
14.
Genetica ; 147(2): 177-183, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30887215

RESUMO

The Kho population speaking Khowar language reside since long ago in Chitral District of North-western Pakistan. So far, no report is available about their genetic structure and relationship with surrounding population groups. We partially sequenced the mitochondrial DNA control region from 16 unrelated Kho male and female individuals of different ages. The D-Loop region sequences of Kho were aligned and compared with the revised Cambridge Reference Sequence (rCRS). The genetic data of Kho was compared with surrounding north-western Pakistani population groups including Pathan, Kashmiri, and Hazara. Comparison with rCRS identified overall 49 different haplotypes for Kho samples. Among these 21 haplotypes were shared by more than one Kho individuals. The genetic diversity and power of discrimination observed for Kho group were 0.215 and 0.202 respectively indicating the Kho tribe as a least differentiated group among north-western Pakistani populations. The haplogroup mapping, phylogenetic and haplotype network analysis revealed the nearby maternal ancestral relationship between Kho and Kashmiri populations. The haplogroups analysis demonstrates the western Eurasian ancestral origin of Kho samples. However, the appearance of a few South Asian haplogroups with low frequency speculate the Kho tribe as an admixed population of western Eurasian and South Asian genetic components.


Assuntos
DNA Mitocondrial/genética , Haplótipos , População/genética , DNA Mitocondrial/química , Frequência do Gene , Migração Humana , Humanos , Paquistão , Linhagem , Sequências Reguladoras de Ácido Nucleico
15.
Genetica ; 147(3-4): 327-335, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31342301

RESUMO

The Sichuan snub-nosed monkey (Rhinopithecus roxellana) is an endangered species endemic to China, where the smallest population resides in Shennongjia National Park, Hubei Province. In this study, the genetic diversity of the Sichuan snub-nosed monkeys from two areas, Qianjiaping (QJP) and Dalongtan (DLT) in Shennongjia National Park was evaluated using single nucleotide polymorphisms (SNPs) data derived from restriction site-associated DNA sequencing (RAD-seq). A total of 41,260 SNP loci were found in 29 Sichuan snub-nosed monkey individuals. The genome-wide nucleotide diversity (π) of the Shennongjia population was 0.001842. The genetic differentiation (FST) between the QJP and DLT subpopulations was 0.034. The heterozygosity of individuals from QJP was 0.3475 ± 0.03696 and 0.3148 ± 0.03501 for individuals from DLT. Although the DLT and QJP subpopulations did not show significant genetic differences, genetic differentiation between the two subpopulations was confirmed using Bayesian cluster analysis, neighbor-joining trees and principal component analysis. These results suggest that the Shennongjia population of Sichuan snub-nosed monkey has relatively low genetic diversity at the genomic level. The little genetic differentiation noted between the DLT and QJP subpopulations likely due to natural and anthropogenic barriers which may exacerbate loss of genetic diversity of this endangered subpopulation.


Assuntos
Variação Genética , Presbytini/genética , Animais , Teorema de Bayes , China , Espécies em Perigo de Extinção , Feminino , Masculino , Parques Recreativos , Filogenia , Polimorfismo de Nucleotídeo Único , População/genética , Análise de Sequência de DNA
16.
Am J Med Genet A ; 179(9): 1846-1856, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31313509

RESUMO

Primary congenital glaucoma (PCG) is a rare but serious birth defect. Genetic mutations have been implicated in the development of PCG, but little is known about nongenetic risk factors. This study investigates potential risk factors for PCG in the National Birth Defects Prevention Study (NBDPS), a large population-based case-control study of major birth defects in the United States. The analysis includes case infants with PCG (N = 107) and control infants without birth defects (N = 10,084) enrolled in NBDPS from birth years 2000-2011. Pregnancy/infant clinical characteristics, demographics, and parental health history were collected through maternal interview. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were computed to examine associations with all PCG cases and isolated PCG cases without other major malformations. Associations with all the cases included term low birth weight (<2,500 g; aOR = 2.80, CI 1.59-4.94), non-Hispanic black maternal race/ethnicity (aOR = 2.42, CI 1.42-4.13), maternal history of seizure (aOR = 2.73, CI 1.25-5.97), maternal antihypertensive use (aOR = 3.60, CI 1.52-8.53), and maternal sexually transmitted infection (aOR = 2.75, CI 1.17-6.44). These factors were also associated with isolated PCG, as was maternal use of nonsteroidal anti-inflammatory drugs (aOR = 2.70, CI 1.15-6.34). This study is among the first to examine a wide array of potential risk factors for PCG in a population-based sample.


Assuntos
Anormalidades Congênitas/epidemiologia , Glaucoma/epidemiologia , População/genética , Adulto , Anti-Inflamatórios não Esteroides/efeitos adversos , Anormalidades Congênitas/genética , Anormalidades Congênitas/patologia , Feminino , Idade Gestacional , Glaucoma/genética , Glaucoma/patologia , Humanos , Lactente , Modelos Logísticos , Masculino , Idade Materna , Mutação , Gravidez , Fatores de Risco
17.
Am J Med Genet A ; 179(9): 1791-1798, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31294928

RESUMO

Achondroplasia is a rare genetic disorder resulting in short-limb skeletal dysplasia. We present the largest European population-based epidemiological study to date using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network. All cases of achondroplasia notified to 28 EUROCAT registries (1991-2015) were included in the study. Prevalence, birth outcomes, prenatal diagnosis, associated anomalies, and the impact of paternal and maternal age on de novo achondroplasia were presented. The study population consisted of 434 achondroplasia cases with a prevalence of 3.72 per 100,000 births (95%CIs: 3.14-4.39). There were 350 live births, 82 terminations of pregnancy after prenatal diagnosis, and two fetal deaths. The prenatal detection rate was significantly higher in recent years (71% in 2011-2015 vs. 36% in 1991-1995). Major associated congenital anomalies were present in 10% of cases. About 20% of cases were familial. After adjusting for maternal age, fathers >34 years had a significantly higher risk of having infants with de novo achondroplasia than younger fathers. Prevalence was stable over time, but regional differences were observed. All pregnancy outcomes were included in the prevalence estimate with 80.6% being live born. The study confirmed the increased risk for older fathers of having infants with de novo achondroplasia.


Assuntos
Acondroplasia/genética , Diagnóstico Pré-Natal , Doenças Raras/epidemiologia , Acondroplasia/diagnóstico , Acondroplasia/epidemiologia , Acondroplasia/patologia , Adulto , Europa (Continente)/epidemiologia , Feminino , Morte Fetal , Humanos , Recém-Nascido , Masculino , Idade Materna , População/genética , Gravidez , Resultado da Gravidez , Doenças Raras/genética , Doenças Raras/patologia
18.
Am J Med Genet A ; 179(9): 1799-1814, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31294918

RESUMO

Sacral agenesis is a rare birth defect characterized by partial or complete absence of the sacrum. We sought to (a) describe case characteristics, (b) estimate birth prevalence, and (c) identify risk factors for nonsyndromic sacral agenesis using data from the National Birth Defects Prevention Study (NBDPS). The NBDPS was a population-based, case-control study involving pregnancies with estimated dates of delivery from October 1997 through December 2011. We estimated birth prevalence using all NBDPS eligible cases. Using self-reported maternal exposure information, we conducted multivariable logistic regression analysis to identify potential risk factors overall and among women without diabetes. The birth prevalence of sacral agenesis was 2.6/100,000 live births. In the multivariable analysis, multifetal pregnancy, pre-existing Type 1 diabetes, and pre-existing Type 2 diabetes were positively and significantly associated with sacral agenesis, albeit estimates were imprecise. Preexisting Type 1 diabetes was the strongest risk factor (adjusted odds ratio = 96.6, 95% confidence interval = 43.5-214.7). Among women without diabetes, periconceptional smoking was positively and significantly associated with sacral agenesis. Our findings underscore the importance of smoking cessation programs among women planning pregnancy and the importance of better understanding the role of glycemic control before and during pregnancy when designing interventions for primary prevention of sacral agenesis.


Assuntos
Anormalidades Múltiplas/epidemiologia , Anormalidades Congênitas/epidemiologia , Diabetes Mellitus/epidemiologia , Meningocele/epidemiologia , Malformações do Sistema Nervoso/epidemiologia , Região Sacrococcígea/anormalidades , Anormalidades Múltiplas/etiologia , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/fisiopatologia , Adulto , Estudos de Casos e Controles , Anormalidades Congênitas/genética , Anormalidades Congênitas/fisiopatologia , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/genética , Complicações do Diabetes/fisiopatologia , Diabetes Mellitus/genética , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Recém-Nascido , Masculino , Exposição Materna , Meningocele/etiologia , Meningocele/genética , Meningocele/fisiopatologia , Malformações do Sistema Nervoso/genética , Malformações do Sistema Nervoso/fisiopatologia , População/genética , Gravidez , Fatores de Risco , Região Sacrococcígea/fisiopatologia , Sacro/anormalidades
19.
BMC Genet ; 19(1): 42, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29986643

RESUMO

BACKGROUND: Atlantic cod (Gadus morhua L.) has formed the basis of many economically significant fisheries in the North Atlantic, and is one of the best studied marine fishes, but a legacy of overexploitation has depleted populations and collapsed fisheries in several regions. Previous studies have identified considerable population genetic structure for Atlantic cod. However, within Norway, which is the country with the largest remaining catch in the Atlantic, the population genetic structure of coastal cod (NCC) along the entire coastline has not yet been investigated. We sampled > 4000 cod from 55 spawning sites. All fish were genotyped with 6 microsatellite markers and Pan I (Dataset 1). A sub-set of the samples (1295 fish from 17 locations) were also genotyped with an additional 9 microsatellites (Dataset 2). Otoliths were read in order to exclude North East Arctic Cod (NEAC) from the analyses, as and where appropriate. RESULTS: We found no difference in genetic diversity, measured as number of alleles, allelic richness, heterozygosity nor effective population sizes, in the north-south gradient. In both data sets, weak but significant population genetic structure was revealed (Dataset 1: global FST = 0.008, P < 0.0001. Dataset 2: global FST = 0.004, P < 0.0001). While no clear genetic groups were identified, genetic differentiation increased among geographically-distinct samples. Although the locus Gmo132 was identified as a candidate for positive selection, possibly through linkage with a genomic region under selection, overall trends remained when this locus was excluded from the analyses. The most common allele in loci Gmo132 and Gmo34 showed a marked frequency change in the north-south gradient, increasing towards the frequency observed in NEAC in the north. CONCLUSION: We conclude that Norwegian coastal cod displays significant population genetic structure throughout its entire range, that follows a trend of isolation by distance. Furthermore, we suggest that a gradient of genetic introgression between NEAC and NCC contributes to the observed population genetic structure. The current management regime for coastal cod in Norway, dividing it into two stocks at 62°N, represents a simplification of the level of genetic connectivity among coastal cod in Norway, and needs revision.


Assuntos
Gadus morhua/genética , Animais , Aquicultura , Genômica , Genótipo , Técnicas de Genotipagem , Repetições de Microssatélites/genética , Noruega , Membrana dos Otólitos/anatomia & histologia , População/genética , Seleção Genética
20.
BMC Genet ; 19(1): 51, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068292

RESUMO

BACKGROUND: The ability of maize populations/landraces to tolerate drastically extreme environments over the past four centuries in Algeria leads to characterize these genetic resources for germplasm management as well as the identification of the best landraces useful for genetic improvement. Thus, the aim of the present work was a fingerprinting of an Algerian maize collection (47 landraces) from Saharan oasis by using 24 agro-morphological traits and18 Simple Sequence Repeats to evaluate genetic diversity and population structure. RESULTS: Phenotypic traits showed large significant variation in which earliness, plant size, ear and kernel features and crop yield appeared the most discriminant traits among landraces by using principal component analysis (PCA). One hundred ninety-seven different alleles were detected with a high mean number of allele per locus (10.9). The selected SSR were highly informative with PIC values > 0.65 as well as an overall genetic diversity (0.47) highlighting a broad genetic variability in the analyzed landraces. Genetic structure analysis revealed a high genetic differentiation among the 47 maize landraces with an overall Fst value (0.33). Cluster analysis for morphological traits as well as for SSR markers grouped the 47 Algerian populations regardless their geographic origin. CONCLUSIONS: Maize from Algerian desert harbors a wide genetic diversity offering a source of novel/unique alleles useful for maize breeding programs to face the ongoing and future major challenge, the climate changes.


Assuntos
Zea mays/classificação , Zea mays/genética , África do Norte , Argélia , Variação Genética , Repetições de Microssatélites , Fenótipo , Filogenia , Melhoramento Vegetal , População/genética
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