scholarly journals Sharp Increase of Problematic Mitogenomes of Birds: Causes, Consequences, and Remedies

2021 ◽  
Vol 13 (9) ◽  
Author(s):  
George Sangster ◽  
Jolanda A Luksenburg
Keyword(s):  
Dna Sequences ◽  
Taxonomic Revision ◽  
Control Measures ◽  
Divergence Times ◽  
Dna Identification ◽  
Sequencing Errors ◽  
The Past ◽  
Quantitative Studies ◽  
Evolutionary Inference ◽  
Phylogenetic Hypotheses

Abstract Authentic DNA sequences are crucial for reliable evolutionary inference. Concerns about the identification of DNA sequences have been voiced several times in the past but few quantitative studies exist. Mitogenomes play important roles in phylogenetics, phylogeography, population genetics, and DNA identification. However, the large number of mitogenomes being published routinely, often in brief data papers, has raised questions about their authenticity. In this study, we quantify problematic mitogenomes of birds and their reusage in other papers. Of 1,876 complete or partial mitogenomes of birds published until January 1, 2020, the authenticity of 1,559 could be assessed with sequences of conspecifics. Of these, 78 (5.0%) were found to be problematic, including 45 curated reference sequences. Problems were due to misidentification (33), chimeras of two or three species (23), sequencing errors/numts (18), incorrect sequence assembly (1), mislabeling at GenBank but not in the final paper (2), or vice versa (1). The number of problematic mitogenomes has increased sharply since 2012. Worryingly, these problematic sequences have been reused 436 times in other papers, including 385 times in phylogenies. No less than 53% of all mitogenomic phylogenies/networks published until January 1, 2020 included at least one problematic mitogenome. Problematic mitogenomes have resulted in incorrect phylogenetic hypotheses and proposals for unwarranted taxonomic revision, and may have compromised comparative analyses and measurements of divergence times. Our results indicate that a major upgrade of quality control measures is warranted. We propose a comprehensive set of measures that may serve as a new standard for publishing mitogenome sequences.

scholarly journals Extensive paraphyly in the typical owl family (Strigidae)

The Auk ◽  
2019 ◽  
Vol 137 (1) ◽  
Author(s):  
Jessie F Salter ◽  
Carl H Oliveros ◽  
Peter A Hosner ◽  
Joseph D Manthey ◽  
Mark B Robbins ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
Protein Coding ◽  
Target Sequencing ◽  
Multispecies Coalescent ◽  
Mitochondrial Data ◽  
Phylogenetic Hypotheses ◽  
Taxonomic Groups ◽  
Analytical Approaches

Abstract The typical owl family (Strigidae) comprises 194 species in 28 genera, 14 of which are monotypic. Relationships within and among genera in the typical owls have been challenging to discern because mitochondrial data have produced equivocal results and because many monotypic genera have been omitted from previous molecular analyses. Here, we collected and analyzed DNA sequences of ultraconserved elements (UCEs) from 43 species of typical owls to produce concatenated and multispecies coalescent-based phylogenetic hypotheses for all but one genus in the typical owl family. Our results reveal extensive paraphyly of taxonomic groups across phylogenies inferred using different analytical approaches and suggest the genera Athene, Otus, Asio, Megascops, Bubo, and Strix are paraphyletic, whereas Ninox and Glaucidium are polyphyletic. Secondary analyses of protein-coding mitochondrial genes harvested from off-target sequencing reads and mitochondrial genomes downloaded from GenBank generally support the extent of paraphyly we observe, although some disagreements exist at higher taxonomic levels between our nuclear and mitochondrial phylogenetic hypotheses. Overall, our results demonstrate the importance of taxon sampling for understanding and describing evolutionary relationships in this group, as well as the need for additional sampling, study, and taxonomic revision of typical owl species. Additionally, our findings highlight how both divergence and convergence in morphological characters have obscured our understanding of the evolutionary history of typical owls, particularly those with insular distributions.

scholarly journals Bayes Estimation of Species Divergence Times and Ancestral Population Sizes Using DNA Sequences From Multiple Loci

Genetics ◽  
2003 ◽  
Vol 164 (4) ◽  
pp. 1645-1656 ◽  
Author(s):  
Bruce Rannala ◽  
Ziheng Yang
Keyword(s):  
Dna Sequences ◽  
Gene Tree ◽  
Species Tree ◽  
Bayes Estimation ◽  
Ancestral Population ◽  
Divergence Times ◽  
Gene Trees ◽  
Species Divergence ◽  
Multiple Loci ◽  
Population Sizes

Abstract The effective population sizes of ancestral as well as modern species are important parameters in models of population genetics and human evolution. The commonly used method for estimating ancestral population sizes, based on counting mismatches between the species tree and the inferred gene trees, is highly biased as it ignores uncertainties in gene tree reconstruction. In this article, we develop a Bayes method for simultaneous estimation of the species divergence times and current and ancestral population sizes. The method uses DNA sequence data from multiple loci and extracts information about conflicts among gene tree topologies and coalescent times to estimate ancestral population sizes. The topology of the species tree is assumed known. A Markov chain Monte Carlo algorithm is implemented to integrate over uncertain gene trees and branch lengths (or coalescence times) at each locus as well as species divergence times. The method can handle any species tree and allows different numbers of sequences at different loci. We apply the method to published noncoding DNA sequences from the human and the great apes. There are strong correlations between posterior estimates of speciation times and ancestral population sizes. With the use of an informative prior for the human-chimpanzee divergence date, the population size of the common ancestor of the two species is estimated to be ∼20,000, with a 95% credibility interval (8000, 40,000). Our estimates, however, are affected by model assumptions as well as data quality. We suggest that reliable estimates have yet to await more data and more realistic models.

scholarly journals Phylogenetic Complexity of Morphologically Identified Anopheles squamosus in Southern Zambia

Insects ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 146
Author(s):  
Jordan Hoffman ◽  
Ilinca Ciubotariu ◽  
Limonty Simubali ◽  
Twig Mudenda ◽  
William Moss ◽  
...  
Keyword(s):  
Phylogenetic Relationships ◽  
Catchment Area ◽  
Control Strategies ◽  
Light Trap ◽  
Current Control ◽  
Control Measures ◽  
Morphological Identification ◽  
The Past ◽  
Blood Meal Source ◽  
Residual Malaria Transmission

Despite dramatic reductions in malaria cases in the catchment area of Macha Hospital, Choma District, Southern Province in Zambia, prevalence has remained near 1–2% by RDT for the past several years. To investigate residual malaria transmission in the area, this study focuses on the relative abundance, foraging behavior, and phylogenetic relationships of Anopheles squamosus specimens. In 2011, higher than expected rates of anthropophily were observed among “zoophilic” An. squamosus, a species that had sporadically been found to contain Plasmodium falciparum sporozoites. The importance of An. squamosus in the region was reaffirmed in 2016 when P. falciparum sporozoites were detected in numerous An. squamosus specimens. This study analyzed Centers for Disease Control (CDC) light trap collections of adult mosquitoes from two collection schemes: one performed as part of a reactive-test-and-treat program and the second performed along a geographical transect. Morphological identification, molecular verification of anopheline species, and blood meal source were determined on individual samples. Data from these collections supported earlier studies demonstrating An. squamosus to be primarily exophagic and zoophilic, allowing them to evade current control measures. The phylogenetic relationships generated from the specimens in this study illustrate the existence of well supported clade structure among An. squamosus specimens, which further emphasizes the importance of molecular identification of vectors. The primarily exophagic behavior of An. squamosus in these collections also highlights that indoor vector control strategies will not be sufficient for elimination of malaria in southern Zambia.

scholarly journals Trends and Source Contribution Characteristics of SO2, NOX, PM10 and PM2.5 Emissions in Sichuan Province from 2013 to 2017

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 189
Author(s):  
Min He ◽  
Junhui Chen ◽  
Yuming He ◽  
Yuan Li ◽  
Qichao Long ◽  
...  
Keyword(s):  
Air Quality ◽  
Sichuan Province ◽  
Control Measures ◽  
So2 Emission ◽  
Source Contribution ◽  
The Past ◽  
Mobile Sources ◽  
Pm10 And Pm2.5 ◽  
Comparison Results ◽  
Pm2.5 Emissions

As one of the most populated regions in China, Sichuan province had been suffering from deteriorated air quality due to the dramatic growth of economy and vehicles in recent years. To deal with the increasingly serious air quality problem, Sichuan government agencies had made great efforts to formulate various control measures and policies during the past decade. In order to better understand the emission control progress in recent years and to guide further control policy formulation, the emission trends and source contribution characteristics of SO2, NOX, PM10 and PM2.5 from 2013 to 2017 were characterized by using emission factor approach in this study. The results indicated that SO2 emission decreased rapidly during 2013–2017 with total emission decreased by 52%. NOX emission decreased during 2013–2015 but started to increase slightly afterward. PM10 and PM2.5 emissions went down consistently during the study period, decreased by 26% and 25%, respectively. In summary, the contribution of power plants kept decreasing, while contribution of industrial combustion remained steady in the past 5 years. The contribution of industrial processes increased for SO2 emission, and decreased slightly for NOX, PM10 and PM2.5 emissions. The on-road mobile sources were the largest emission contributor for NOX, accounting for about 32–40%, and its contribution increased during 2013–2015 and then decreased. It was worth mentioning that nonroad mobile sources and natural gas fired boilers were becoming important NOX contributors in Sichuan. Fugitive dust were the key emission sources for PM10 and PM2.5, and the contribution kept increasing in the study period. Comparison results with other inventories, satellite data and ground observations indicated that emission trends developed in this research were relatively credible.

Detection of Flaviviral-Like DNA Sequences in Aedes aegypti (Diptera: Culicidae) Collected From Argentina

2021 ◽  
Author(s):  
Melisa B Bonica ◽  
Dario E Balcazar ◽  
Ailen Chuchuy ◽  
Jorge A Barneche ◽  
Carolina Torres ◽  
...  
Keyword(s):  
Public Health ◽  
Aedes Aegypti ◽  
Dna Sequences ◽  
Immature Stages ◽  
Public Health Burden ◽  
The Past ◽  
Health Burden ◽  
The World ◽  
Aegypti Genome ◽  
Dengue Epidemics

Abstract Diseases caused by flaviviruses are a major public health burden across the world. In the past decades, South America has suffered dengue epidemics, the re-emergence of yellow fever and St. Louis encephalitis viruses, and the introduction of West Nile and Zika viruses. Many insect-specific flaviviruses (ISFs) that cannot replicate in vertebrate cells have recently been described. In this study, we analyzed field-collected mosquito samples from six different ecoregions of Argentina to detect flaviviruses. We did not find any RNA belonging to pathogenic flaviviruses or ISFs in adults or immature stages. However, flaviviral-like DNA similar to flavivirus NS5 region was detected in 83–100% of Aedes aegypti (L.). Despite being previously described as an ancient element in the Ae. aegypti genome, the flaviviral-like DNA sequence was not detected in all Ae. aegypti samples and sequences obtained did not form a monophyletic group, possibly reflecting the genetic diversity of mosquito populations in Argentina.

scholarly journals Data Structures to Represent a Set of k -long DNA Sequences

2021 ◽  
Vol 54 (1) ◽  
pp. 1-22
Author(s):  
Rayan Chikhi ◽  
Jan Holub ◽  
Paul Medvedev
Keyword(s):  
Data Structures ◽  
Dna Sequences ◽  
Sequencing Data ◽  
String Algorithms ◽  
Fixed Length ◽  
The Past

The analysis of biological sequencing data has been one of the biggest applications of string algorithms. The approaches used in many such applications are based on the analysis of k -mers, which are short fixed-length strings present in a dataset. While these approaches are rather diverse, storing and querying a k -mer set has emerged as a shared underlying component. A set of k -mers has unique features and applications that, over the past 10 years, have resulted in many specialized approaches for its representation. In this survey, we give a unified presentation and comparison of the data structures that have been proposed to store and query a k -mer set. We hope this survey will serve as a resource for researchers in the field as well as make the area more accessible to researchers outside the field.

scholarly journals Genome sequence, transcriptome, and annotation of rodent malaria parasite Plasmodium yoelii nigeriensis N67

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Cui Zhang ◽  
Cihan Oguz ◽  
Sue Huse ◽  
Lu Xia ◽  
Jian Wu ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Malaria Parasite ◽  
Vaccine Development ◽  
De Novo ◽  
Gene Families ◽  
Plasmodium Yoelii ◽  
Control Measures ◽  
Effective Control ◽  
Malaria Parasites ◽  
Rodent Malaria

Abstract Background Rodent malaria parasites are important models for studying host-malaria parasite interactions such as host immune response, mechanisms of parasite evasion of host killing, and vaccine development. One of the rodent malaria parasites is Plasmodium yoelii, and multiple P. yoelii strains or subspecies that cause different disease phenotypes have been widely employed in various studies. The genomes and transcriptomes of several P. yoelii strains have been analyzed and annotated, including the lethal strains of P. y. yoelii YM (or 17XL) and non-lethal strains of P. y. yoelii 17XNL/17X. Genomic DNA sequences and cDNA reads from another subspecies P. y. nigeriensis N67 have been reported for studies of genetic polymorphisms and parasite response to drugs, but its genome has not been assembled and annotated. Results We performed genome sequencing of the N67 parasite using the PacBio long-read sequencing technology, de novo assembled its genome and transcriptome, and predicted 5383 genes with high overall annotation quality. Comparison of the annotated genome of the N67 parasite with those of YM and 17X parasites revealed a set of genes with N67-specific orthology, expansion of gene families, particularly the homologs of the Plasmodium chabaudi erythrocyte membrane antigen, large numbers of SNPs and indels, and proteins predicted to interact with host immune responses based on their functional domains. Conclusions The genomes of N67 and 17X parasites are highly diverse, having approximately one polymorphic site per 50 base pairs of DNA. The annotated N67 genome and transcriptome provide searchable databases for fast retrieval of genes and proteins, which will greatly facilitate our efforts in studying the parasite biology and gene function and in developing effective control measures against malaria.

scholarly journals Violence and discrimination among Ugandan residents during the COVID-19 lockdown

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Elizabeth Katana ◽  
Bob Omoda Amodan ◽  
Lilian Bulage ◽  
Alex R. Ario ◽  
Joseph Nelson Siewe Fodjo ◽  
...  
Keyword(s):  
Law Enforcement ◽  
Control Measures ◽  
Sub Saharan Africa ◽  
World Health ◽  
Vulnerable Groups ◽  
Transport Systems ◽  
Outcome Variable ◽  
Cross Sectional ◽  
Factors Associated ◽  
The Past

Abstract Background In March 2020, the World Health Organization (WHO) declared COVID-19 a pandemic. Many countries in Sub-Saharan Africa, Uganda inclusive, implemented lockdowns, curfew, banning of both private and public transport systems, and mass gatherings to minimize spread. Social control measures for COVID-19 are reported to increase violence and discrimination globally, including in Uganda as some may be difficult to implement resulting in the heavy deployment of law enforcement. Media reports indicated that cases of violence and discrimination had increased in Uganda’s communities following the lockdown. We estimated the incidence and factors associated with experiencing violence and discrimination among Ugandans during the COVID-19 lockdown to inform control and prevention measures. Methods In April 2020, we conducted a secondary analysis of cross-sectional data under the International Citizen Project (ICP) to assess adherence to public health measures and their impact on the COVID-19 outbreak in Uganda. We analyzed data on violence and discrimination from the ICP study. We performed descriptive statistics for all the participants’ characteristics and created a binary outcome variable called experiencing violence and/or discrimination. We performed logistic regression analysis to identify the factors associated with experiencing violence and discrimination. Results Of the 1726 ICP study participants, 1051 (58.8%) were males, 841 (48.7%) were currently living with a spouse or partner, and 376 (21.8%) had physically attended work for more than 3 days in the past week. Overall, 145 (8.4%) experienced any form of violence and/or discrimination by any perpetrator, and 46 (31.7%) of the 145 reported that it was perpetrated by a law enforcement officer. Factors associated with experiencing violence or discrimination were: being male (AOR = 1.60 CI:1.10–2.33), having attended work physically for more than 3 days in the past week (AOR = 1.52 CI:1.03–2.23), and inability to access social or essential health services since the epidemic started (AOR = 3.10 CI:2.14–4.50). Conclusion A substantial proportion of Ugandan residents experienced violence and/or discrimination during the COVID-19 lockdown, mostly perpetrated by law enforcement officers. We recommend mitigation of the collateral impact of lockdowns with interventions that focus on improving policing quality, ensuring continuity of essential services, and strengthening support systems for vulnerable groups including males.

scholarly journals Leishmaniasis: Current Status of Vaccine Development

2001 ◽  
Vol 14 (2) ◽  
pp. 229-243 ◽  
Author(s):  
Emanuela Handman
Keyword(s):  
Dna Sequences ◽  
Vaccine Development ◽  
Development Program ◽  
Skin Lesions ◽  
Mononuclear Phagocytes ◽  
Control Measures ◽  
Host Susceptibility ◽  
Current Status ◽  
Dna Encoding ◽  
And Control

SUMMARY Leishmaniae are obligatory intracellular protozoa in mononuclear phagocytes. They cause a spectrum of diseases, ranging in severity from spontaneously healing skin lesions to fatal visceral disease. Worldwide, there are 2 million new cases each year and 1/10 of the world's population is at risk of infection. To date, there are no vaccines against leishmaniasis and control measures rely on chemotherapy to alleviate disease and on vector control to reduce transmission. However, a major vaccine development program aimed initially at cutaneous leishmaniasis is under way. Studies in animal models and humans are evaluating the potential of genetically modified live attenuated vaccines, as well as a variety of recombinant antigens or the DNA encoding them. The program also focuses on new adjuvants, including cytokines, and delivery systems to target the T helper type 1 immune responses required for the elimination of this intracellular organism. The availability, in the near future, of the DNA sequences of the human and Leishmania genomes will extend the vaccine program. New vaccine candidates such as parasite virulence factors will be identified. Host susceptibility genes will be mapped to allow the vaccine to be targeted to the population most in need of protection.

Skin as a Source of Nosocomial Infection: Directions for Future Research

1986 ◽  
Vol 7 (S2) ◽  
pp. 113-117 ◽  
Author(s):  
Dennis G. Maki
Keyword(s):  
Clinical Trials ◽  
Nosocomial Infection ◽  
Scientific Data ◽  
Control Measures ◽  
Future Research ◽  
Controlled Clinical Trials ◽  
Nosocomial Pathogens ◽  
The Past ◽  
Infection Control Measures ◽  
Per Se

Whereas infections of the skin per se comprise only a fraction of all institutionally-acquired infections, the skin has become one of the most important reservoirs of nosocomial pathogens in the hospital. Professor Noble has provided a scholarly review of the increasing importance of the major constituents of the cutaneous microflora as nosocomial pathogens and what we know of their epidemiology. Unfortunately, the empiricism and limited scientific data which underlie essential infection control measures in this area, particularly in regard to cutaneous antisepsis and handwashing, is almost incongruous in an era in which controlled clinical trials have dominated most other areas of medicine. The numerous outbreaks traced to contaminated antiseptics and disinfectants over the past two decades, stand as mute testimony to the inadequate investigative attention this area has received.

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