Pf7: an open dataset of genome variation in 20,000 worldwide samples.

We describe the MalariaGEN Pf7 data resource, the seventh release of genome variation data from the MalariaGEN network.  It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented.  For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations.

The use of video job-aids to improve the quality of seasonal malaria chemoprevention delivery.

Mobile phones are increasingly used in community health programmes, but the use of video job-aids that can be displayed on smart phones has not been widely exploited. We investigated the use of video job-aids to support the delivery of seasonal malaria chemoprevention (SMC) in countries in West and Central Africa. The study was prompted by the need for training tools that could be used in a socially distanced manner during the COVID-19 pandemic.

Microsatellite genotyping and genome-wide single nucleotide polymorphism-based indices of Plasmodium falciparum diversity within clinical infections.

Background: In regions where malaria is endemic, individuals are often infected with multiple distinct parasite genotypes, a situation that may impact on evolution of parasite virulence and drug resistance. Most approaches to studying genotypic diversity have involved analysis of a modest number of polymorphic loci, although whole genome sequencing enables a broader characterisation of samples.

Methods: PCR-based microsatellite typing of a panel of ten loci was performed on Plasmodium falciparum in 95 clinical isolates from a highly endemic area in the Republic of Guinea, to characterize within-isolate genetic diversity.

Genome-wide analysis of selection on the malaria parasite Plasmodium falciparum in West African populations of differing infection endemicity.

Locally varying selection on pathogens may be due to differences in drug pressure, host immunity, transmission opportunities between hosts, or the intensity of between-genotype competition within hosts. Highly recombining populations of the human malaria parasite Plasmodium falciparum throughout West Africa are closely related, as gene flow is relatively unrestricted in this endemic region, but markedly varying ecology and transmission intensity should cause distinct local selective pressures. Genome-wide analysis of sequence variation was undertaken on a sample of 100 P.

Breakdown in the process of incipient speciation in Anopheles gambiae.

Understanding genetic causes and effects of speciation in sympatric populations of sexually reproducing eukaryotes is challenging, controversial, and of practical importance for controlling rapidly evolving pests and pathogens. The major African malaria vector mosquito Anopheles gambiae sensu stricto (s.s.

Population genetic structure of Plasmodium falciparum across a region of diverse endemicity in West Africa.

Background: Malaria parasite population genetic structure varies among areas of differing endemicity, but this has not been systematically studied across Plasmodium falciparum populations in Africa where most infections occur.

Methods: Ten polymorphic P. falciparum microsatellite loci were genotyped in 268 infections from eight locations in four West African countries (Republic of Guinea, Guinea Bissau, The Gambia and Senegal), spanning a highly endemic forested region in the south to a low endemic Sahelian region in the north.

High prevalence of hemoglobin disorders and glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Republic of Guinea (West Africa).

Reliable and accurate epidemiological data is a prerequisite for a cost effective screening program for inherited disorders, which however, is lacking in a number of developing countries. Here we report the first detailed population study in the Republic of Guinea, a sub-Saharan West African country, designed to assess the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency and hemoglobinopathies, including screening for thalassemia. Peripheral blood samples from 187 Guinean adults were screened for hemoglobin (Hb) variants by standard hematological methods.

Biological validation of self-reported condom use among sex workers in Guinea.

Self-reported condom use may be prone to social desirability bias. Our aim was to assess the validity of self-reported condom use in a population of female sex workers using prostate specific antigen (PSA) as a gold standard biomarker of recent unprotected vaginal intercourse. We collected data on 223 sex-workers in Conakry, Guinea in order to assess the sensitivity and specificity of self-reported condom use as well as to examine the predictors of discordance between self-report and PSA presence.

Effects of prenatal methylmercury exposure on brain monoamine oxidase activity and neurobehaviour of rats.

Monoamine oxidase (MAO) regulates levels of dopamine, serotonin, and noradrenaline in the nervous tissue and is required for proper neuronal development. The purpose of this study was to determine if oral exposure of adult female rats to methylmercury (MeHg) at 0.5 or 1 mg/kg/day before and during pregnancy would affect MAO activity in various brain regions of the offspring.

An interspecies comparison of mercury inhibition on muscarinic acetylcholine receptor binding in the cerebral cortex and cerebellum.

Mercury (Hg) is a ubiquitous pollutant that can disrupt neurochemical signaling pathways in mammals. It is well documented that inorganic Hg (HgCl(2)) and methyl Hg (MeHg) can inhibit the binding of radioligands to the muscarinic acetylcholine (mACh) receptor in rat brains. However, little is known concerning this relationship in specific anatomical regions of the brain or in other species, including humans.