Mutations in Plasmodium falciparum K13 propeller gene from Bangladesh (2009–2013)

Abstract

BackgroundBangladesh is a malaria hypo-endemic country sharing borders with India and Myanmar. Artemisinin combination therapy (ACT) remains successful in Bangladesh. An increase of artemisinin-resistant malaria parasites on the Thai-Cambodia and Thai-Myanmar borders is worrisome. K13 propeller gene (PF3D7_1343700 or PF13_0238) mutations have been linked to both in vitro artemisinin resistance and in vivo slow parasite clearance rates. This group undertook to evaluate if mutations seen in Cambodia have emerged in Bangladesh where ACT use is now standard for a decade.MethodsSamples were obtained from Plasmodium falciparum-infected malaria patients from Upazila health complexes (UHC) between 2009 and 2013 in seven endemic districts of Bangladesh. These districts included Khagrachari (Matiranga UHC), Rangamati (Rajasthali UHC), Cox’s Bazar (Ramu and Ukhia UHC), Bandarban (Lama UHC), Mymensingh (Haluaghat UHC), Netrokona (Durgapur and Kalmakanda UHC), and Moulvibazar (Sreemangal and Kamalganj UHC).ResultsOut of 296 microscopically positive P. falciparum samples, 271 (91.6%) were confirmed as mono-infections by both real-time PCR and nested PCR. The K13 propeller gene from 253 (93.4%) samples was sequenced bi-directionally. One non-synonymous mutation (A578S) was found in Bangladeshi clinical isolates. The A578S mutation was confirmed and lies adjacent to the C580Y mutation, the major mutation causing delayed parasite clearance in Cambodia. Based on computational modeling A578S should have a significant effect on tertiary structure of the protein.ConclusionThe data suggest that P. falciparum in Bangladesh remains free of the C580Y mutation linked to delayed parasite clearance. However, the mutation A578S is present and based on structural analysis could affect K13 gene function. Further in vivo clinical studies are required to validate the effect of this mutation.

Little Polymorphism at the K13 Propeller Locus in Worldwide Plasmodium falciparum Populations Prior to the Introduction of Artemisinin Combination Therapies

“…Of these, A569T was previously observed only in Kenya, where it was present in a single sample, as in our analysis (24). In contrast, the A578S polymorphism is present in Africa (8,(24)(25)(26)(27)(28) and Bangladesh (29). Conflicting findings have been reported regarding the role of A578S in artemisinin resistance (8,26,30).…”

K13 Kelch Propeller Domain and mdr1 Sequence Polymorphism in Field Isolates From Northeast Region, India

“…Different crosssectional studies have described the scenario of prevailing and predominating K13 mutations in SEA, particularly, C580Y has reached fixation at the Myanmar-Thailand border and M476I prevailing in eastern border of Myanmar. 8,14,19,22,24,46,47 In this study, neither C580Y nor M476I allele has been recorded in circulating isolates within this region. Moreover, evidence of F446I mutation in recent study indicates that it has either emerged in this region or spread from near most foci.…”

“…8 But accumulation of data over time suggests that mutations in this gene vary geographically and mostly in accordance with the employed antimalarial regimens. [14][15][16][17][18][19][20][21] In a recent study, non-reference K13 mutations viz., 584V, 580Y, 574L, 568G, 553L, 543T, 539T, 493H, 481V, 449A, 255K, and 189T have been found involved in prolonged parasite clearance, and it was also stated that artemisinin resistance in SEA has emerged independently without sweeping from Cambodia. 22 In 2016, most of them became either validated or candidate K13 mutation for artemisinin resistance.…”

Plasmodium falciparum Genetic Diversity in Bangladesh Does Not Suggest a Hypoendemic Population Structure

“…Administration of antimalarial drugs may force the local parasite population toward a new resistant phenotype by mutation in certain genes, 6 such mutation has been reported from two of the samples of this study. 22 Since the study areas are populated by people of different ethnic groups, 2 this might present different host immune systems for the parasite to withstand, which could generate high genetic diversity. 6 Despite WHO recommendations for the use of msp1, msp2, and glurp as markers in drug efficacy studies 29 and their limited use in the drug efficacy studies in CHT areas of Bangladesh, 19,20 the circulating P. falciparum population genetic structure is still unknown.…”

“…All samples were taken from a study that has been described elsewhere. 22 Nested-PCR and real-time PCR were done as described previously. 23,24 The study was approved by the Institutional Ethics Review Committee of the International Center for Diarrhoeal Disease Research, Bangladesh.…”