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Stanley P, Rajkumari N, Sivaradjy M. Molecular detection of antimalarial resistance in Plasmodium vivax isolates from a tertiary care setting in Puducherry. Indian J Med Microbiol 2024; 47:100496. [PMID: 37949233 DOI: 10.1016/j.ijmmb.2023.100496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/14/2023] [Accepted: 10/18/2023] [Indexed: 11/12/2023]
Abstract
PURPOSE The study was aimed at detecting the mutation patterns in the drug targets in Plasmodium vivax that confer resistance to the common antimalarial agents used in India. METHODS A total of 27 Plasmodium vivax isolates collected from whole blood samples over a three year period were subjected to PCR amplification followed by sequencing of the genes pvmdr1, pvdhfr, pvdhps and pvk12, which serve as the molecular targets to detect resistance to chloroquine, pyrimethamine, sulfadoxine and artemisinin respectively. RESULTS The study found T958 M F1076L double mutants of pvmdr1 in 52 %(14/27) isolates, S58R S117 N double mutants of pvdhfr in 67 % (18/27) isolates, A383G A553G double mutant pvdhps in 59 % (16/27) isolates and wild type of pvk12 gene in all the isolates. CONCLUSIONS There was a rise in the proportion of double mutants of pvmdr1 and pvdhfr over time. Those cases with double mutant pvmdr1 gene in their isolates were found to have a prolonged hospital stay compared to those without, indicating reduced clinical response to chloroquine.
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Affiliation(s)
- Pheba Stanley
- Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Dhanvantri Nagar, Puducherry, 605006, India.
| | - Nonika Rajkumari
- Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Dhanvantri Nagar, Puducherry, 605006, India.
| | - Monika Sivaradjy
- Department of Microbiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Dhanvantri Nagar, Puducherry, 605006, India; Department of Microbiology, ESIC Medical College& PGIMSR, Chennai, 78, India.
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Suphakhonchuwong N, Rungsihirunrat K, Kuesap J. Surveillance of drug resistance molecular markers in Plasmodium vivax before and after introduction of dihydroartemisinin and piperaquine in Thailand: 2009-2019. Parasitol Res 2023; 122:2871-2883. [PMID: 37725258 DOI: 10.1007/s00436-023-07977-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 09/12/2023] [Indexed: 09/21/2023]
Abstract
Resistance to antimalarial drugs is a serious issue around the world. Widespread Plasmodium vivax and P. falciparum coinfections are commonly found in Thailand. Dihydroartemisinin and piperaquine (DHA-PPQ) have been used as first-line treatments for P. falciparum since 2015, and chloroquine (CQ) and primaquine (PQ) have remained first-line drugs for P. vivax for more than 60 years. Coinfections may lead parasites to evolve with regard to genetics under selective drug pressure. This study is aimed at investigating genes linked to antimalarial resistance in P. vivax before and after introduction of DHA-PPQ as a new drug regimen in Thailand. A total of 400 P. vivax isolates were collected from samples along the Thai-Myanmar and Thai-Malaysian borders before (2009-2015) and after (2016-2019) introduction of DHA-PPQ. Genomic DNA of P. vivax was obtained and subjected to analysis of five drug resistance-associated genes (Pvdhfr, Pvdhps, Pvmdr1, Pvcrt-o, and PvK12) by nested polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and nucleotide sequencing. A high prevalence of Pvdhfr was found in both endemic areas over the period. The quadruple (57I/58R/61M/117T) Pvdhfr haplotype was predominant in both periods in both endemic areas. Although the wild-type haplotype of Pvdhps was predominant in Thai-Malaysian isolates in both periods, a single mutant haplotype (383G) was dominant in Thai-Myanmar isolates during both periods. A low prevalence of the Pvmdr1 976F mutation was found in both periods among Thai-Myanmar isolates. A significant decrease in Pvmdr1 976F was identified in Thai-Malaysian isolates from the second period (p < 0.01). Only one nonsynonymous mutation of Pvcrt-o (193E) and one synonymous mutation of PvK12 (R584) were detected in four isolates (4.7%) and one isolate (0.5%) in the first period among Thai-Myanmar isolates, respectively. Thus, with limited clinical efficacy data, the low prevalence of drug-resistance markers may suggest that there is a low prevalence of P. vivax-resistant strains and that the current drug regimen for P. vivax is still effective for treating this P. vivax parasite population. Continued surveillance of antimalarial drug resistance markers and monitoring of clinical drug efficacy should be conducted for epidemiological and policy implications.
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Affiliation(s)
| | | | - Jiraporn Kuesap
- Faculty of Allied Health Sciences, Thammasat University, Pathumthani, 12120, Thailand.
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Ding H, Dong Y, Deng Y, Xu Y, Liu Y, Wu J, Chen M, Zhang C, Liu L, Lin Y. Molecular surveillance of chloroquine resistance in Plasmodium vivax isolates from malaria cases in Yunnan Province of China using pvcrt-o gene polymorphisms. Malar J 2023; 22:338. [PMID: 37940956 PMCID: PMC10631137 DOI: 10.1186/s12936-023-04776-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 10/31/2023] [Indexed: 11/10/2023] Open
Abstract
BACKGROUND The efficacy of chloroquine treatment for vivax malaria has been rarely evaluated due to a lack of an appropriate testing method. The objective of this study was to conduct molecular monitoring of chloroquine resistance in Plasmodium vivax strains from vivax malaria patients in Yunnan Province, focusing on the analysis of polymorphism in the P. vivax chloroquine resistance transporter protein orthologous gene (pvcrt-o). METHODS In accordance with the principles of a cohort study, blood samples were collected from malaria cases diagnosed with a P. vivax mono-infection in Yunnan Province from 2020 to 2022. Segmental PCR was used to amplify the whole pvcrt-o gene in the blood samples and their products were subsequently sequenced. The sequencing data were arranged to obtain the full coding DNA sequence (CDS) as well as the gene's promoter region sequences. The CDSs were aligned with the reference sequence (XM_001613407.1) of the P. vivax SalI isolate to identify the mutant loci. RESULTS From a total of 375 blood samples taken from vivax malaria cases, 272 both whole gene CDSs (1272-1275 bp) and promoter DNA sequences (707 bp) of pvcrt-o gene were obtained. Among the whole CDSs, there were 7 single nucleotide polymorphic sites in which c.7 A>G was the minor allele frequency (MAF) site with 4.4% (12/272) detection rate. The mutation detection rate showed a significant decrease from 9.8% (10/102) in 2020 to 1.1% (1/92) in 2021 and 1.3% (1/78) in 2022, indicating statistical significance (χ2 = 11.256, P < 0.05). Among the identified 12 haplotypes, the majority of which were wild type (75.7%; 206/272). These four mutant haplotypes (Hap_3, Hap_5, Hap_9, and Hap_10) were classified as "K10 insertion type" and accounted for 12.1% (33/272). The detection rate of Hap_3 increased from 1.0% (1/102) in 2020 to 13.0% (12/92) in 2021 and 14.1% (11/78) in 2022, indicating statistical significance. A total of 23.8% (65/272) of the samples exhibited 14 bp (bp) deletions in the promoter region, occurring most frequently in the wild type haplotype (Hap_1) samples at a rate of 28.6% (59/206). CONCLUSIONS In recent years in Yunnan Province, a notable proportion of vivax malaria patients are infected by P. vivax strains with a "K10 insertion" and partial sequence deletions in the promoter region of the pvcrt-o gene, necessitating vigilance.
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Affiliation(s)
- Hongyun Ding
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, China
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Ying Dong
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China.
| | - Yan Deng
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Yanchun Xu
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Yan Liu
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Jing Wu
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Mengni Chen
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Canglin Zhang
- Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Yunnan International Joint Laboratory of Tropical Infectious Diseases, Yunnan Institute of Parasitic Diseases Control, Pu'er, 665000, China
| | - Li Liu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, China.
| | - Yingkun Lin
- Center for Disease Control and Prevention, Dehong, 678499, China.
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Cui L, Sattabongkot J, Aung PL, Brashear A, Cao Y, Kaewkungwal J, Khamsiriwatchara A, Kyaw MP, Lawpoolsri S, Menezes L, Miao J, Nguitragool W, Parker D, Phuanukoonnon S, Roobsoong W, Siddiqui F, Soe MT, Sriwichai P, Yang Z, Zhao Y, Zhong D. Multidisciplinary Investigations of Sustained Malaria Transmission in the Greater Mekong Subregion. Am J Trop Med Hyg 2022; 107:138-151. [PMID: 36228909 DOI: 10.4269/ajtmh.21-1267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 05/28/2022] [Indexed: 11/07/2022] Open
Abstract
In the course of malaria elimination in the Greater Mekong Subregion (GMS), malaria epidemiology has experienced drastic spatiotemporal changes with residual transmission concentrated along international borders and the rising predominance of Plasmodium vivax. The emergence of Plasmodium falciparum parasites resistant to artemisinin and partner drugs renders artemisinin-based combination therapies less effective while the potential spread of multidrug-resistant parasites elicits concern. Vector behavioral changes and insecticide resistance have reduced the effectiveness of core vector control measures. In recognition of these problems, the Southeast Asian International Center of Excellence for Malaria Research (ICEMR) has been conducting multidisciplinary research to determine how human migration, antimalarial drug resistance, vector behavior, and insecticide resistance sustain malaria transmission at international borders. These efforts allow us to comprehensively understand the ecology of border malaria transmission and develop population genomics tools to identify and track parasite introduction. In addition to employing in vivo, in vitro, and molecular approaches to monitor the emergence and spread of drug-resistant parasites, we also use genomic and genetic methods to reveal novel mechanisms of antimalarial drug resistance of parasites. We also use omics and population genetics approaches to study insecticide resistance in malaria vectors and identify changes in mosquito community structure, vectorial potential, and seasonal dynamics. Collectively, the scientific findings from the ICEMR research activities offer a systematic view of the factors sustaining residual malaria transmission and identify potential solutions to these problems to accelerate malaria elimination in the GMS.
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Affiliation(s)
- Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | | | | | - Awtum Brashear
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Yaming Cao
- Department of Immunology, China Medical University, Shenyang, China
| | | | | | | | | | - Lynette Menezes
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Jun Miao
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Wang Nguitragool
- Mahidol Vivax Research Unit, Mahidol University, Bangkok, Thailand
| | - Daniel Parker
- Department of Epidemiology, University of California at Irvine, Irvine, California
| | | | | | - Faiza Siddiqui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Myat Thu Soe
- Myanmar Health Network Organization, Yangon, Myanmar
| | - Patchara Sriwichai
- Department of Medical Entomology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yan Zhao
- Department of Immunology, China Medical University, Shenyang, China
| | - Daibin Zhong
- Program in Public Health, University of California at Irvine, Irvine, California
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Huang F, Li S, Tian P, Pu LJS, Cui Y, Liu H, Yang L, Bi DY. Genetic polymorphisms in genes associated with drug resistance in Plasmodium vivax parasites from northeastern Myanmar. Malar J 2022; 21:66. [PMID: 35241080 PMCID: PMC8892751 DOI: 10.1186/s12936-022-04084-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 02/11/2022] [Indexed: 11/10/2022] Open
Abstract
Background Anti-malarial drug resistance is still a major threat to malaria elimination in the Great Mekong Sub-region. Plasmodium vivax parasites resistant to anti-malarial drugs are now found in Myanmar. Molecular surveillance on drug resistance genes in P. vivax parasites from northeastern Myanmar was aimed at estimating the underlying drug resistance in this region. Methods Blood samples from patients with vivax malaria were collected from Laiza city in northeastern Myanmar in 2020. Drug resistance genes including Pvcrt-o, Pvmdr1, Pvdhfr and Pvdhps were amplified and sequenced. Genetic polymorphisms and haplotypes were analysed to evaluate the prevalence of mutant alleles associated with drug resistance. Results A total of 149 blood samples from P. vivax patients were collected. The prevalence of Pvmdr1 mutations at codons 958 and 1076 was 100.0% and 52.0%, respectively, whereas no single nucleotide polymorphism was present at codon 976. The proportions of single and double mutant types were 48.0% and 52.0%, respectively. A K10 “AAG” insertion in the Pvcrt-o gene was not detected. Mutations in Pvdhfr at codons 57, 58, 61, 99 and 117 were detected in 29.9%, 54.3%, 27.6%, 44.9% and 55.1% of the samples, respectively. Wild type was predominant (46.3%), followed by quadruple and double mutant haplotypes. Of three types of tandem repeat variations of Pvdhfr, Type B, with three copies of GGDN repeats, was the most common. Pvdhps mutations were only detected at codons 383 and 553 and the wild type Pvdhps was dominant (78.0%). Eleven haplotypes were identified when combining the mutations of Pvdhfr and Pvdhps, among which the predominant one was the wild type (33.9%), followed by double mutant alleles S58R/S117N /WT (24.6%). Conclusions This study demonstrated resistant P. vivax phenotypes exists in northeastern Myanmar. Continued surveillance of drug resistance markers is needed to update treatment guidelines in this region. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04084-y.
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Affiliation(s)
- Fang Huang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China. .,Chinese Center for Tropical Diseases Research, Shanghai, China. .,NHC Key Laboratory of Parasite and Vector Biology, Shanghai, China. .,WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Shanghai, China.
| | - Shigang Li
- Yingjiang County Center for Disease Control and Prevention, Yingjiang, Yunnan, China
| | - Peng Tian
- Yunnan Institute of Parasitic Diseases, Pu'er, Yunnan, China
| | | | - Yanwen Cui
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China.,Chinese Center for Tropical Diseases Research, Shanghai, China.,NHC Key Laboratory of Parasite and Vector Biology, Shanghai, China.,WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Shanghai, China
| | - Hui Liu
- Yunnan Institute of Parasitic Diseases, Pu'er, Yunnan, China
| | - Lianzhi Yang
- Nabang Township Hospital, Yingjiang, Yunnan, China
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Zeng W, Zhao H, Zhao W, Yang Q, Li X, Li X, Duan M, Wang X, Li C, Xiang Z, Chen X, Cui L, Yang Z. Molecular Surveillance and Ex Vivo Drug Susceptibilities of Plasmodium vivax Isolates From the China-Myanmar Border. Front Cell Infect Microbiol 2021; 11:738075. [PMID: 34790586 PMCID: PMC8591282 DOI: 10.3389/fcimb.2021.738075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/06/2021] [Indexed: 11/18/2022] Open
Abstract
Drug resistance in Plasmodium vivax may pose a challenge to malaria elimination. Previous studies have found that P. vivax has a decreased sensitivity to antimalarial drugs in some areas of the Greater Mekong Sub-region. This study aims to investigate the ex vivo drug susceptibilities of P. vivax isolates from the China–Myanmar border and genetic variations of resistance-related genes. A total of 46 P. vivax clinical isolates were assessed for ex vivo susceptibility to seven antimalarial drugs using the schizont maturation assay. The medians of IC50 (half-maximum inhibitory concentrations) for chloroquine, artesunate, and dihydroartemisinin from 46 parasite isolates were 96.48, 1.95, and 1.63 nM, respectively, while the medians of IC50 values for piperaquine, pyronaridine, mefloquine, and quinine from 39 parasite isolates were 19.60, 15.53, 16.38, and 26.04 nM, respectively. Sequence polymorphisms in pvmdr1 (P. vivax multidrug resistance-1), pvmrp1 (P. vivax multidrug resistance protein 1), pvdhfr (P. vivax dihydrofolate reductase), and pvdhps (P. vivax dihydropteroate synthase) were determined by PCR and sequencing. Pvmdr1 had 13 non-synonymous substitutions, of which, T908S and T958M were fixed, G698S (97.8%) and F1076L (93.5%) were highly prevalent, and other substitutions had relatively low prevalences. Pvmrp1 had three non-synonymous substitutions, with Y1393D being fixed, G1419A approaching fixation (97.8%), and V1478I being rare (2.2%). Several pvdhfr and pvdhps mutations were relatively frequent in the studied parasite population. The pvmdr1 G698S substitution was associated with a reduced sensitivity to chloroquine, artesunate, and dihydroartemisinin. This study suggests the possible emergence of P. vivax isolates resistant to certain antimalarial drugs at the China–Myanmar border, which demands continuous surveillance for drug resistance.
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Affiliation(s)
- Weilin Zeng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Hui Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Wei Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Qi Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xinxin Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xiaosong Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Mengxi Duan
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xun Wang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Cuiying Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Zheng Xiang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xi Chen
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
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Zeng W, Wang S, Feng S, Zhong D, Hu Y, Bai Y, Ruan Y, Si Y, Zhao H, Yang Q, Li X, Chen X, Zhang Y, Li C, Xiang Z, Wu Y, Chen F, Su P, Rosenthal BM, Yang Z. Polymorphism of Antifolate Drug Resistance in Plasmodium vivax From Local Residents and Migrant Workers Returned From the China-Myanmar Border. Front Cell Infect Microbiol 2021; 11:683423. [PMID: 34249776 PMCID: PMC8265503 DOI: 10.3389/fcimb.2021.683423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 06/03/2021] [Indexed: 11/29/2022] Open
Abstract
Drug-resistant Plasmodium vivax malaria impedes efforts to control, eliminate, and ultimately eradicate malaria in Southeast Asia. P. vivax resistance to antifolate drugs derives from point mutations in specific parasite genes, including the dihydropteroate synthase (pvdhps), dihydrofolate reductase (pvdhfr), and GTP cyclohydrolase I (pvgch1) genes. This study aims to investigate the prevalence and spread of drug resistance markers in P. vivax populating the China-Myanmar border. Blood samples were collected from symptomatic patients with acute P. vivax infection. Samples with single-clone P. vivax infections were sequenced for pvdhps and pvdhfr genes and genotyped for 6 flanking microsatellite markers. Copy number variation in the pvgch1 gene was also examined. Polymorphisms were observed in six different codons of the pvdhps gene (382, 383, 512, 549, 553, and 571) and six different codons of the pvdhfr gene (13, 57, 58, 61, 99, 117) in two study sites. The quadruple mutant haplotypes 57I/L/58R/61M/117T of pvdhfr gene were the most common (comprising 76% of cases in Myitsone and 43.7% of case in Laiza). The double mutant haplotype 383G/553G of pvdhps gene was also prevalent at each site (40.8% and 31%). Microsatellites flanking the pvdhfr gene differentiated clinical samples from wild type and quadruple mutant genotypes (FST= 0.259-0.3036), as would be expected for a locus undergoing positive selection. The lack of copy number variation of pvgch1 suggests that SP-resistant P. vivax may harbor alternative mechanisms to secure sufficient folate.
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Affiliation(s)
- Weilin Zeng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Siqi Wang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Shi Feng
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Daibin Zhong
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, United States
| | - Yue Hu
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yao Bai
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yonghua Ruan
- Department of Pathology, Kunming Medical University, Kunming, China
| | - Yu Si
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Hui Zhao
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Qi Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xinxin Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Xi Chen
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yanmei Zhang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Cuiying Li
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Zheng Xiang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Yanrui Wu
- Department of Cell Biology and Medical Genetics, Kunming Medical University, Kunming, China
| | - Fang Chen
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
| | - Pincan Su
- Transfusion Medicine Research Department, Yunnan Kunming Blood Center, Kunming, China
| | - Benjamin M Rosenthal
- Animal Parasitic Disease Laboratory, Agricultural Research Service, US Department of Agriculture, Beltsville, MD, United States
| | - Zhaoqing Yang
- Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China
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