The microbiological paradigm for surveillance of diverse pathogens requires knowledge of the variation of the major surface antigen under the most intense immune selection as immune responses to these antigens drive transmission dynamics. This creates a pathway for population genetics/genomics to be combined with mathematical modelling to describe transmission dynamics to inform public health policy. Here we consider how we can bring population genetics and population dynamics together for a highly recombining pathogen like Plasmodium falciparum.
View Article and Find Full Text PDFMixed-species, mixed-strain infections are known to occur in humans in malaria endemic areas. To date, the true extent of this complexity has not been explored in high-burden countries of sub-Saharan Africa. Here we take a metagenomic lens to infections obtained by sampling variable blood volumes from residents living in high, seasonal transmission in northern Ghana.
View Article and Find Full Text PDFThe var multigene family encodes Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), central to host-parasite interactions. Genome structure studies have identified three major groups of var genes by specific upstream sequences (upsA, B, or C). Var with these ups groups have different chromosomal locations, transcriptional directions, and associations with disease severity.
View Article and Find Full Text PDFThe multigene family encodes the erythrocyte membrane protein 1 (PfEMP1), which is important in host-parasite interaction as a virulence factor and major surface antigen of the blood stages of the parasite, responsible for maintaining chronic infection. Whilst important in the biology of , these genes (50 to 60 genes per parasite genome) are routinely excluded from whole genome analyses due to their hyper-diversity, achieved primarily through recombination. The PfEMP1 head structure almost always consists of a DBLα-CIDR tandem.
View Article and Find Full Text PDFPanels of informative biallelic single nucleotide polymorphisms (SNPs) have been proposed to be an economical method to fast-track the population genetic analysis of in malaria-endemic areas. Whilst used successfully in low-transmission areas where infections are monoclonal and highly related, we present the first study to evaluate the performance of these 24- and 96-SNP molecular barcodes in African countries, characterised by moderate-to-high transmission, where multiclonal infections are prevalent. For SNP barcodes it is generally recommended that the SNPs chosen i) are biallelic, ii) have a minor allele frequency greater than 0.
View Article and Find Full Text PDFHere we introduce a new endpoint "census population size" to evaluate the epidemiology and control of infections, where the parasite, rather than the infected human host, is the unit of measurement. To calculate census population size, we rely on a definition of parasite variation known as multiplicity of infection (MOI ), based on the hyper-diversity of the multigene family. We present a Bayesian approach to estimate MOI from sequencing and counting the number of unique DBLα tags (or DBLα types) of genes, and derive from it census population size by summation of MOI in the human population.
View Article and Find Full Text PDFPLoS Comput Biol
January 2023
At a time when effective tools for monitoring malaria control and eradication efforts are crucial, the increasing availability of molecular data motivates their application to epidemiology. The multiplicity of infection (MOI), defined as the number of genetically distinct parasite strains co-infecting a host, is one key epidemiological parameter for evaluating malaria interventions. Estimating MOI remains a challenge for high-transmission settings where individuals typically carry multiple co-occurring infections.
View Article and Find Full Text PDFOil spills pose a significant threat to marine biodiversity. Crude oil can partition into sediments where it may be persistent, placing benthic species such as decapods at particular risk of exposure. Transcriptomic and histological tools are often used to investigate the effects of hydrocarbon exposure on marine organisms following oil spill events, allowing for the identification of metabolic pathways impacted by oil exposure.
View Article and Find Full Text PDFThe evolution of Australia's distinctive marsupial fauna has long been linked to the onset of continent-wide aridity. However, how this profound climate change event affected the diversification of extant lineages is still hotly debated. Here, we assemble a DNA sequence dataset of Macropodoidea-the clade comprising kangaroos and their relatives-that incorporates a complete mitogenome for the Desert 'rat-kangaroo', Caloprymnus campestris.
View Article and Find Full Text PDFThe enormous diversity and complexity of genes that diversify rapidly by recombination has led to the exclusion of assembly of these genes from major genome initiatives (e.g., Pf6).
View Article and Find Full Text PDFWorldwide, rising ocean temperatures are causing declines and range shifts in marine species. The direct effects of climate change on the biology of marine organisms are often well documented; yet, knowledge on the indirect effects, particularly through trophic interactions, is largely lacking. We provide evidence of ocean warming decoupling critical trophic interactions supporting a commercially important mollusc in a climate change hotspot.
View Article and Find Full Text PDFFront Endocrinol (Lausanne)
January 2022
Body composition (fat, skeletal muscle and bone mass) is an important determinant of overall health and risk of endocrine disorders such as type 2 diabetes and osteoporosis. Although diet and physical activity are strongly implicated, body composition is also heritable. We conducted a discovery genome-wide association study on 31 phenotypes from the three-compartment body composition model (fat, lean and bone mass) in a set of 4 386 individuals (n = 2 109 males, n = 2 294 females) from the UK Biobank pilot imaging enhancement program that underwent a dual energy X-ray absorptiometry (DXA) scan for assessment of body composition and genetic screening.
View Article and Find Full Text PDFLabyrinthula spp. are saprobic, marine protists that also act as opportunistic pathogens and are the causative agents of seagrass wasting disease (SWD). Despite the threat of local- and large-scale SWD outbreaks, there are currently gaps in our understanding of the drivers of SWD, particularly surrounding Labyrinthula spp.
View Article and Find Full Text PDFFreshwater catfish of the genus , known as the airbreathing catfish, are widespread and important for food security through small scale inland fisheries and aquaculture. Limited genomic data are available for this important group of fishes. The bighead catfish () is a commercial aquaculture species in southeast Asia used for aquaculture and threatened in its natural environment through habitat destruction, over-exploitation and competition from other introduced species of .
View Article and Find Full Text PDFThe rice leaf mitochondrial DNA is more methylated compared to the rice grain mitochondrial DNA. The old rice leaf mitochondrial DNA has also a higher methylation level than the young rice leaf mitochondrial DNA. The presence of DNA methylation in rice organelles has not been well characterized.
View Article and Find Full Text PDFThe emergence of cost-effective and rapid sequencing approaches has resulted in an exponential rise in the number of mitogenomes on public databases in recent years, providing greater opportunity for undertaking large-scale comparative genomic and systematic research. Nonetheless, current datasets predominately come from small and disconnected studies on a limited number of related species, introducing sampling biases and impeding research of broad taxonomic relevance. This study contributes 21 crustacean mitogenomes from several under-represented decapod infraorders including Polychelida and Stenopodidea, which are used in combination with 225 mitogenomes available on NCBI to investigate decapod mitogenome diversity and phylogeny.
View Article and Find Full Text PDFCharacterising adaptive genetic divergence among conspecific populations is often achieved by studying genetic variation across defined environmental gradients. In marine systems this is challenging due to a paucity of information on habitat heterogeneity at local and regional scales and a dependency on sampling regimes that are typically limited to broad longitudinal and latitudinal environmental gradients. As a result, the spatial scales at which selection processes operate and the environmental factors that contribute to genetic adaptation in marine systems are likely to be unclear.
View Article and Find Full Text PDFMar Genomics
October 2019
Crude oil is a key contaminant in aquatic environments entering via natural and anthropogenic sources, causing toxicity in marine organisms. Traditionally, biomarkers have been utilised to determine crude oil exposure and effects in aquatic organisms, however advances in genomic technologies has led to increased adoption of transcriptomic approaches for identifying response and detoxification pathways following contaminant exposure. This study presents the first transcriptome for the greentail prawn (Metapenaeus bennettae), a commercially targeted benthic decapod crustacean from eastern and south-eastern Australia.
View Article and Find Full Text PDFGrain amyloplast and leaf chloroplast DNA sequences are identical in rice plants but are differentially methylated. The leaf chloroplast DNA becomes more methylated as the rice plant ages. Rice is an important crop worldwide.
View Article and Find Full Text PDFThe infraorder Anomura consists of a morphologically and ecologically heterogeneous group of decapod crustaceans, and has attracted interest from taxonomists for decades attempting to find some order out of the seemingly chaotic diversity within the group. Species-level diversity within the Anomura runs the gamut from the "hairy" spindly-legged yeti crab found in deep-sea hydrothermal vent environments to the largest known terrestrial invertebrate, the robust coconut or robber crab. Owing to a well-developed capacity for parallel evolution, as evidenced by the occurrence of multiple independent carcinization events, Anomura has long tested the patience and skill of both taxonomists attempting to find order, and phylogeneticists trying to establish stable hypotheses of evolutionary inter-relationships.
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