Browsing by Author "Apinjoh, T."
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Item K13-propeller polymorphisms in plasmodium falciparum parasites from sub-saharan Africa(Journal of Infectious Diseases, 2015-01) Kamau, E.; Campino, S.; Amenga-Etego, L.; Drury, E.; Ishengoma, D.; Johnson, K.; Mumba, D.; Kekre, M.; Yavo, W.; Mead, D.; Bouyou-Akotet, M.; Apinjoh, T.; Golassa, L.; Randrianarivelojosia, M.; Andagalu B, B.; Maiga-Ascofare, O.; Amambua-Ngwa, A.; Tindana, P.; Ghansah, A.; Macinnis, B.; Kwiatkowski, D.; Djimde, A.A.Mutations in the Plasmodium falciparum K13-propeller domain have recently been shown to be important determinants of artemisinin resistance in Southeast Asia. This study investigated the prevalence of K13-propeller polymorphisms across sub-Saharan Africa. A total of 1212 P. falciparum samples collected from 12 countries were sequenced. None of the K13-propeller mutations previously reported in Southeast Asia were found, but 22 unique mutations were detected, of which 7 were nonsynonymous. Allele frequencies ranged between 1% and 3%. Three mutations were observed in >1 country, and the A578S was present in parasites from 5 countries. This study provides the baseline prevalence of K13-propeller mutations in sub-Saharan Africa. © 2015 The Author. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.Item Major subpopulations of Plasmodium falciparum in sub-Saharan Africa(Science, 2019-08-23) Amenga-Etego, L.; Amambua-Ngwa, A.; Kamau, E.; Amato, R.; Ghansah, A.; Golassa, L.; Randrianarivelojosia, M.; Ishengoma, D.; Apinjoh, T.; Maïga-Ascofaré, O.; Andagalu, B.; Yavo, W.; Bouyou-Akotet, M.; Kolapo, O.; Mane, K.; Worwui, A.; Jeffries, D.; Simpson, V.; D’Alessandro, U.; Kwiatkowski, D.; Djimde, A.A.Understanding genomic variation and population structure of Plasmodium falciparum across Africa is necessary to sustain progress toward malaria elimination. Genome clustering of 2263 P. falciparum isolates from 24 malaria-endemic settings in 15 African countries identified major western, central, and eastern ancestries, plus a highly divergent Ethiopian population. Ancestry aligned to these regional blocs, overlapping with both the parasite’s origin and with historical human migration. The parasite populations are interbred and shared genomic haplotypes, especially across drug resistance loci, which showed the strongest recent identity-by-descent between populations. A recent signature of selection on chromosome 12 with candidate resistance loci against artemisinin derivatives was evident in Ghana and Malawi. Such selection and the emerging substructure may affect treatment-based intervention strategies against P. falciparum malaria.Item Monitoring parasite diversity for malaria elimination in sub-Saharan Africa(Science, 2014-09) Ghansah, A.; Amenga-Etego, L.; Amambua-Ngwa, A.; Andagalu, B.; Apinjoh, T.; Bouyou-Akotet, M.; Cornelius, V.; Golassa, L.; Andrianaranjaka, V.H.; Ishengoma, D.; Johnson, K.; Kamau, E.; Maïga-Ascofaré, O.; Mumba, D.; Tindana, P.; Tshefu-Kitoto, A.; Randrianarivelojosia, M.; William, Y.; Kwiatkowski, D.P.; Djimde, A.A.The African continent continues to bear the greatest burden of malaria and the greatest diversity of parasites, mosquito vectors, and human victims. The evolutionary plasticity of malaria parasites and their vectors is a major obstacle to eliminating the disease. Of current concern is the recently reported emergence of resistance to the front-line drug, artemisinin, in South-East Asia in Plasmodium falciparum, which calls for preemptive surveillance of the African parasite population for genetic markers of emerging drug resistance. Here we describe the Plasmodium Diversity Network Africa (PDNA), which has been established across 11 countries in sub-Saharan Africa to ensure that African scientists are enabled to work together and to play a key role in the global effort for tracking and responding to this public health threat.Item An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples(2021) MalariaGEN; Ahouidi, A.; Ali, M.; Almagro-Garcia, J.; Amambua-Ngwa, A.; Amaratunga, C.; Amato, R.; Amenga-Etego, L.; Andagalu, B.; Anderson, T.J.C.; Andrianaranjaka, V.; Apinjoh, T.; Ariani, C.; Ashley, E.A.; Auburn, S.; Awandare, G.A.; Ba, H.; Baraka, V.; Barry, A.E.; Bejon, P.; Bertin, G.I.; Boni, M.F.; Borrmann, S.; Bousema, T.; Branch, O.; Bull, P.C.; Busby, G.B.J.; Chookajorn, T.; Chotivanich, K.; Claessens, A.; Conway, D.; Craig, A.; D'Alessandro, U.; Dama, S.; Day, N.P.J.; Denis, B.; Diakite, M.; Djimdé, A.; Dolecek, C.; Dondorp, A.M.; Drakeley, C.; Drury, E.; Duffy, P.; Echeverry, D.F.; Egwang, T.G.; Erko, B.; Fairhurst, R.M.; Faiz, A.; Fanello, C.A.; Fukuda, M.M.; Gamboa, D.; Ghansah, A.; Golassa, L.; Goncalves, S.; Hamilton, W.L.; Harrison, G.L.A.; Hart, L.; Henrichs, C.; Hien, T.T.; Hill, C.A.; Hodgson, A.; Hubbart, C.; Imwong, M.; Ishengoma, D.S.; Jackson, S.A.; Jacob, C.G.; Jeffery, B.; Jeffreys, A.E.; Johnson, K.J.; Jyothi, D.; Kamaliddin, C.; Kamau, E.; Kekre, M.; Kluczynski, K.; Kochakarn, T.; Konaté, A.; Kwiatkowski, D.P.; Kyaw, M.P.; Lim, P.; Lon, C.; Loua, K.M.; Maïga-Ascofaré, O.; Malangone, C.; Manske, M.; Marfurt, J.; Marsh, K.; Mayxay, M.; Miles, A.; Miotto, O.; Mobegi, V.; Mokuolu, O.A.; Montgomery, J.; Mueller, I.; Newton, P.N.; Nguyen, T.; Nguyen, T.; Noedl, H.; Nosten, F.; Noviyanti, R.; Nzila, A.; Ochola-Oyier, L.I.; Ocholla, H.; Oduro, A.; Omedo, I.; Onyamboko, M.A.; Ouedraogo, J.; Oyebola, K.; Pearson, R.D.; Peshu, N.; Phyo, A.P.; Plowe, C.V.; Price, R.N.; Pukrittayakamee, S.; Randrianarivelojosia, M.; Rayner, J.C.; Ringwald, P.; Rockett, K.A.; Rowlands, K.; Ruiz, L.; Saunders, D.; Shayo, A.; Siba, P.; Simpson, V.J.; Stalker, J.; Su, X.; Sutherland, C.; Takala-Harrison, S.; Tavul, L.; Thathy, V.; Tshefu, A.; Verra, F.; Vinetz, J.; Wellems, T.E.; Wendler, J.; White, N.J.; Wright, I.; Yavo, W.; Ye, H.MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.Item Plasmodium malariae structure and genetic diversity in sub‑Saharan Africa determined from microsatellite variants and linked SNPs in orthologues of antimalarial resistance genes(Scientific reports, 2022) Oriero, E.C.; Demba, M.A.; Diop, M.F.; Ishengoma, D.S.; Amenga‑Etego, L.N.; Ghansah, A.; Apinjoh, T.; Issiaka, S.Plasmodium malariae, a neglected human malaria parasite, contributes up to 10% of malaria infections in sub-Saharan Africa (sSA). Though P. malariae infection is considered clinically benign, it presents mostly as coinfections with the dominant P. falciparum. Completion of its reference genome has paved the way to further understand its biology and interactions with the human host, including responses to antimalarial interventions. We characterized 75 P. malariae isolates from seven endemic countries in sSA using highly divergent microsatellites. The P. malariae infections were highly diverse and five subpopulations from three ancestries (independent of origin of isolates) were determined. Sequences of 11 orthologous antimalarial resistance genes, identifed low frequency single nucleotide polymorphisms (SNPs), strong linkage disequilibrium between loci that may be due to antimalarial drug selection. At least three sub-populations were detectable from a subset of denoised SNP data from mostly the mitochondrial cytochrome b coding region. This evidence of diversity and selection calls for including P. malariae in malaria genomic surveillance towards improved tools and