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Donkeys (Equus asinus) have been used extensively in agriculture and transportations since their domestication, ca. 5000-7000 years ago, but the increased mechanization of the last century has largely spoiled their role as burden animals, particularly in developed countries. Consequently, donkey breeds and population sizes have been declining for decades, and the diversity contributed by autochthonous gene pools has been eroded. Here, we examined coding-region data extracted from 164 complete mitogenomes and 1392 donkey mitochondrial DNA (mtDNA) control-region sequences to (i) assess worldwide diversity, (ii) evaluate geographical patterns of variation, and (iii) provide a new nomenclature of mtDNA haplogroups. The topology of the Maximum Parsimony tree confirmed the two previously identified major clades, i.e. Clades 1 and 2, but also highlighted the occurrence of a deep-diverging lineage within Clade 2 that left a marginal trace in modern donkeys. Thanks to the identification of stable and highly diagnostic coding-region mutational motifs, the two lineages were renamed as haplogroup A and haplogroup B, respectively, to harmonize clade nomenclature with the standard currently adopted for other livestock species. Control-region diversity and population expansion metrics varied considerably between geographical areas but confirmed North-eastern Africa as the likely domestication center. The patterns of geographical distribution of variation analyzed through phylogenetic networks and AMOVA confirmed the co-occurrence of both haplogroups in all sampled populations, while differences at the regional level point to the joint effects of demography, past human migrations and trade following the spread of donkeys out of the domestication center. Despite the strong decline that donkey populations have undergone for decades in many areas of the world, the sizeable mtDNA variability we scored, and the possible identification of a new early radiating lineage further stress the need for an extensive and large-scale characterization of donkey nuclear genome diversity to identify hotspots of variation and aid the conservation of local breeds worldwide.
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DNA Mitocondrial , Equidae , Variação Genética , Haplótipos , Filogenia , Dinâmica Populacional , Animais , Equidae/genética , Equidae/classificação , DNA Mitocondrial/genética , Domesticação , Genoma MitocondrialRESUMO
The diversity in genome resources is fundamental to designing genomic strategies for local breed improvement and utilisation. These resources also support gene discovery and enhance our understanding of the mechanisms of resilience with applications beyond local breeds. Here, we report the genome sequences of 555 cattle (208 of which comprise new data) and high-density (HD) array genotyping of 1,082 samples (537 new samples) from indigenous African cattle populations. The new sequences have an average genome coverage of ~30X, three times higher than the average (~10X) of the over 300 sequences already in the public domain. Following variant quality checks, we identified approximately 32.3 million sequence variants and 661,943 HD autosomal variants mapped to the Bos taurus reference genome (ARS-UCD1.2). The new datasets were generated as part of the Centre for Tropical Livestock Genetics and Health (CTLGH) Genomic Reference Resource for African Cattle (GRRFAC) initiative, which aspires to facilitate the generation of this livestock resource and hopes for its utilisation for complete indigenous breed characterisation and sustainable global livestock improvement.
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Genoma , Bovinos/genética , Animais , Genômica , África , Cruzamento , Variação GenéticaRESUMO
Fasciola gigantica is a widespread parasite that causes neglected disease in livestock worldwide. Its high transmissibility and dispersion are attributed to its ability to infect intermediate snail hosts and adapt to various mammalian definitive hosts. This study investigated the variation and population dynamics of F. gigantica in cattle, sheep, and goats from three states in Sudan. Mitochondrial cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 1 (ND1) genes were sequenced successfully to examine intra and interspecific differences. ND1 exhibited higher diversity than COI, with 15 haplotypes and 10 haplotypes, respectively. Both genes had high haplotype diversity but low nucleotide diversity, with 21 and 11 polymorphic sites for ND1 and COI, respectively. Mismatch distribution analysis and neutrality tests revealed that F. gigantica from different host species was in a state of population expansion. Maximum likelihood phylogenetic trees and median networks revealed that F. gigantica in Sudan and other African countries had host-specific and country-specific lineages for both genes. The study also indicated that F. gigantica-infected small ruminants were evolutionarily distant, suggesting deep and historical interspecies adaptation.
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Complexo IV da Cadeia de Transporte de Elétrons , Fasciola , Fasciolíase , Variação Genética , Cabras , Haplótipos , NADH Desidrogenase , Filogenia , Dinâmica Populacional , Animais , Sudão/epidemiologia , Fasciola/genética , Fasciola/classificação , Fasciola/isolamento & purificação , Fasciolíase/veterinária , Fasciolíase/parasitologia , Fasciolíase/epidemiologia , Ovinos/parasitologia , Cabras/parasitologia , Bovinos , NADH Desidrogenase/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças das Cabras/parasitologia , Doenças das Cabras/epidemiologia , Ruminantes/parasitologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Análise de Sequência de DNARESUMO
The mosquito Aedes aegypti is the primary vector of many human arboviruses such as dengue, yellow fever, chikungunya, and Zika, which affect millions of people worldwide. Population genetic studies on this mosquito have been important in understanding its invasion pathways and success as a vector of human disease. The Axiom aegypti1 SNP chip was developed from a sample of geographically diverse A. aegypti populations to facilitate genomic studies on this species. We evaluate the utility of the Axiom aegypti1 SNP chip for population genetics and compare it with a low-depth shotgun sequencing approach using mosquitoes from the native (Africa) and invasive ranges (outside Africa). These analyses indicate that results from the SNP chip are highly reproducible and have a higher sensitivity to capture alternative alleles than a low-coverage whole-genome sequencing approach. Although the SNP chip suffers from ascertainment bias, results from population structure, ancestry, demographic, and phylogenetic analyses using the SNP chip were congruent with those derived from low-coverage whole-genome sequencing, and consistent with previous reports on Africa and outside Africa populations using microsatellites. More importantly, we identified a subset of SNPs that can be reliably used to generate merged databases, opening the door to combined analyses. We conclude that the Axiom aegypti1 SNP chip is a convenient, more accurate, low-cost alternative to low-depth whole-genome sequencing for population genetic studies of A. aegypti that do not rely on full allelic frequency spectra. Whole-genome sequencing and SNP chip data can be easily merged, extending the usefulness of both approaches.
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Aedes , Genética Populacional , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma , Aedes/genética , Animais , Sequenciamento Completo do Genoma/métodos , Filogenia , Genoma de Inseto , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Genótipo , Técnicas de Genotipagem/métodos , Mosquitos Vetores/genéticaRESUMO
INTRODUCTION: The Ovar-DRB1 gene, a crucial element of the Major Histocompatibility Complex (MHC) Class II region, initiates adaptive immunity by presenting antigens to T-cells. Genetic diversity in sheep, particularly in MHC Class II genes like Ovar-DRB1, directly influences the specturm of presented antigens impacting immune responses and disease susceptability. Understanding the allelic diversity of Ovar-DRB1 gene in Sudan Desert Sheep (SDS) is essential for uncovering the genetic basis of immune responses and disease resistance, given the the breeds significance in Sudan's unique environment. METHODS: Utilizing Targeted Next-Generation Sequencing (NGS) we explore allelic diversity in Ovar-DRB1 gene within SDS. Successfully ampliying and and sequencing the second exon of this gene in 288 SDS samples representing six breeds provided a comprehensive allelic profile, enabling a detalied examination of the gene's genetic makeup. RESULTS: We identifed forty-six alleles, including four previously unreported, enrichness the genetic diversity of SDS breeds. These alleles exhibiting non-uniform distribution, varying frequencies across breeds, indicating a breed-specific genetic landscape. Certain alleles, known and novel, show higher frequencies in specific populations, suggesting potential associations with adaptive immune responses. Identifying these alleles sets the stage for investigating their functional roles and implications for disease resistance. Genetic differentiation among SDS breeds, as indicated by FST values and clustering analyses, highlights a unique genetic makeup shaped by geographic and historical factors. These differentiation patterns among SDS breeds have broader implications for breed conservation and targeted breeding to enhance disease resistance in specific populations. CONCLUSION: This study unveils Ovar-DRB1 gene allelic diversity in SDS breeds through targeted NGS and genetic analyses, revealing new alleles that underscore the breeds' unique genetic profile. Insights into the genetic factors governing immune responses and disease resistance emerge, promising for optimization of breeding strategies for enhanced livestock health in Sudan's unique environment.
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Resistência à Doença , Variação Genética , Ovinos/genética , Animais , Resistência à Doença/genética , Sudão , Antígenos de Histocompatibilidade Classe II/genética , Alelos , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
More than 400 million sheep are raised on the African continent, the majority of which are indigenous and are primarily reared for sustenance. They have effectively adapted to various climatic and production environments, surviving and flourishing. The genetic relationships among these sheep populations remain understudied. Herein, we sequenced the entire mitochondrial DNA control region of 120 animals from Hamary and Kabashi and their crossbreed (Hamary x Kabashi) of Sudan desert sheep (SDS) to understand their maternal-inherited genetic variation and demographic history profiles and relate those to the history of sheep pastoralism on the African continent. The results show a diversified and predominant D- loop haplogroup B (n = 102, 85%), with all other sequences belonging to haplogroup A. Most of the maternal genetic variation was partitioned between haplogroup (76.3%) while within haplogroup accounted for 23.7% of the variation. However, little genetic differentiation was observed among the two breeds and their crosses, with our results supporting a Hamari maternal origin for the crossbreed. Bayesian coalescent-based analysis reveals distinct demographic history between the two haplogroups, two breeds and their crosses. Comparison of the two haplogroup showed that haplogroup B experienced an earlier expansion than haplogroup A. Unlike the breed-based comparison, the expansion of the two breeds started roughly at the same time, around 6500 years ago, with Kabashi having a slightly greater effective population size. The maternal ancestors of SDS may have diverged before their introduction to the African continent. This study provides novel insights into the early history of these two main breeds of Sudan desert sheep and their crosses.
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DNA Mitocondrial , Variação Genética , Ovinos/genética , Animais , Sudão , Teorema de Bayes , Filogenia , Haplótipos , DNA Mitocondrial/genética , Densidade DemográficaRESUMO
BACKGROUND: Indigenous Sudanese cattle are mainly indicine/zebu (humped) type. They thrive in the harshest dryland environments characterised by high temperatures, long seasonal dry periods, nutritional shortages, and vector disease challenges. Here, we sequenced 60 indigenous Sudanese cattle from six indigenous breeds and analysed the data using three genomic scan approaches to unravel cattle adaptation to the African dryland region. RESULTS: We identified a set of gene-rich selective sweep regions, detected mostly on chromosomes 5, 7 and 19, shared across African and Gir zebu. These include genes involved in immune response, body size and conformation, and heat stress response. We also identified selective sweep regions unique to Sudanese zebu. Of these, a 250 kb selective sweep on chromosome 16 spans seven genes, including PLCH2, PEX10, PRKCZ, and SKI, which are involved in alternative adaptive metabolic strategies of insulin signalling, glucose homeostasis, and fat metabolism. CONCLUSIONS: Our results suggest that environmental adaptation may involve recent and ancient selection at gene-rich regions, which might be under a common regulatory genetic control, in zebu cattle.
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Genoma , Polimorfismo de Nucleotídeo Único , Adaptação Fisiológica/genética , Animais , Sequência de Bases , Bovinos/genética , Genômica/métodosRESUMO
Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic arboviral disease that poses a great threat to global health in the Old World, and it is endemic in Europe, Asia, and Africa, including Sudan. In this retrospective study, we reviewed previous epidemiological reports about the major epidemics of CCHF throughout Sudan between 2010 and 2020. During these epidemics, the infection of humans with Crimean-Congo hemorrhagic fever virus (CCHFV), the causative agent of CCHF, was diagnosed using qRT-PCR. We have identified 88 cases of CCHF, including 13 fatalities reported during five epidemics that occurred in 2010, 2011, 2015, 2019, and 2020. The two epidemics in 2010 and 2011 were by far the largest, with 51 and 27 cases reported, respectively. The majority of cases (78%) were reported in the endemic region of Kordofan. Here, we document that the first emergence of CCHFV in the Darfur region, West Sudan, occurred in 2010. We were not able to investigate outbreak dynamics through phylogenetic analysis due to the limited diagnostic capacity and the lack of sequencing services in the country. These findings call for establishing a genomic-based integrated One Health surveillance and response system for the early preparedness, prevention, and control of CCHF in the country.
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Increases in arbovirus outbreaks in Sudan are vectored by Aedes aegypti, raising the medical importance of this mosquito. We genotyped 12 microsatellite loci in four populations of Ae. aegypti from Sudan, two from the East and two from the West, and analyzed them together with a previously published database of 31 worldwide populations to infer population structure and investigate the demographic history of this species in Sudan. Our results revealed the presence of two genetically distinct subspecies of Ae. aegypti in Sudan. These are Ae. aegypti aegypti in Eastern Sudan and Ae. aegypti formosus in Western Sudan. Clustering analysis showed that mosquitoes from East Sudan are genetically homogeneous, while we found population substructure in West Sudan. In the global context our results indicate that Eastern Sudan populations are genetically closer to Asian and American populations, while Western Sudan populations are related to East and West African populations. Approximate Bayesian Computation Analysis supports a scenario in which Ae. aegypti entered Sudan in at least two independent occasions nearly 70-80 years ago. This study provides a baseline database that can be used to determine the likely origin of new introductions for this invasive species into Sudan. The presence of the two subspecies in the country should be consider when designing interventions, since they display different behaviors regarding epidemiologically relevant parameters, such as blood feeding preferences and ability to transmit disease.
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Western Baggara cattle breed (WBCB) is an East African zebu inhabiting Sudan, well-known as beef-producing cattle. We investigated herein two phenotypically and geographically distinct populations of this breed, namely Nyalawi and Daeinawi, which are renowned for their unique meat production capabilities and adaptation attributes, with the aim to contribute to our understanding of their maternal genetic diversity and demography dynamics. Genetic polymorphism analysis of the full-length D-loop mtDNA region revealed 44 and 35 polymorphic sites defining 28 and 24 distinct haplotypes in the Nyalawi and the Daeinawi, respectively. Observed genetic diversity is high within the population with a low level of genetic differentiation between populations. Approximate Bayesian computation via the calculation of Bayesian skyline plots and neutrality tests support past expansion with a higher maternal effective population size (Ne ) in Nyalawi compared with the Daeinawi population and a population expansion beginning around 4,500 YBP and 3,500 YBP, respectively, before the arrival of zebu into the continent.
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Bovinos , DNA Mitocondrial , Variação Genética , Animais , Teorema de Bayes , Bovinos/genética , DNA Mitocondrial/genética , Haplótipos , Filogenia , Densidade Demográfica , SudãoRESUMO
Tick-borne hemoparasitic (TBH) infections are a major problem affecting livestock industries worldwide, particularly in tropical and subtropical regions. This study was carried out in response to repeated reports from local veterinarians in Khartoum State, Sudan, where TBH infections are prevalent in dairy farms. This cross-sectional study was undertaken from October 2017 to April 2018 with the objective of assessing the prevalence and potential risk factors associated with cattle anaplasmosis and babesiosis in the localities of Omdurman, Khartoum, and Khartoum North, Khartoum State. A total of 292 cattle blood samples collected from apparently healthy animals were examined for the presence of A. marginale, Babesia bigemina, and B. bovis using PCR. The overall prevalence of A. marginale and B. bigemina was found to be 40.41% and 3.42%, respectively, while B. bovis was not detected. Mixed infections with A. marginale and B. bigemina were detected in four (1.37%) cattle. The prevalence of the two pathogens was found to be significantly higher in Khartoum and Omdurman than in Khartoum North. However, no significant difference was observed for the prevalence based on sex, age, breed, and mean packed cell volume values. Our findings indicated that A. marginale is a highly prevalent parasite in Khartoum State, which may be a primary constraint to the cattle industry. Inclusion of this pathogen in the diagnostic protocols, and consequent treatment and tick control are necessary. Moreover, the role of B. bigemina infection may exacerbate the situation to some extent in this region.
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Anaplasma marginale , Anaplasmose , Babesiose , Doenças dos Bovinos , Theileriose , Doenças Transmitidas por Carrapatos , Anaplasma marginale/genética , Anaplasmose/epidemiologia , Animais , Babesiose/epidemiologia , Babesiose/parasitologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Estudos Transversais , Sudão/epidemiologia , Theileriose/epidemiologia , Theileriose/parasitologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/veterináriaRESUMO
The emergence of the Asian invasive malaria vector, Anopheles stephensi, has been identified in Khartoum, the capital city of Sudan. This is the first report that confirms the geographical expansion of this urban mosquito into Central Sudan. We urgently recommend the launch of a national entomological survey to determine the distribution of this invasive disease vector and to generate essential information about its bionomics and susceptibility to available malaria control measures.
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Distribuição Animal , Anopheles/genética , Anopheles/parasitologia , Malária/transmissão , Mosquitos Vetores/genética , Mosquitos Vetores/parasitologia , Animais , Anopheles/classificação , Cidades , Humanos , Malária/prevenção & controle , Mosquitos Vetores/classificação , Filogenia , SudãoRESUMO
Autochthonous Sudanese cattle breeds, namely Baggara for beef and Butana and Kenana for dairy, are characterized by their adaptive characteristics and high performance in hot and dry agro-ecosystems. They are thus used largely by nomadic and semi-nomadic pastoralists. We analyzed the diversity and genetic structure of the BoLA-DRB3 gene, a genetic locus linked to the immune response, for the indigenous cattle of Sudan and in the context of the global cattle repository. Blood samples (n = 225) were taken from three indigenous breeds (Baggara; n = 113, Butana; n = 60 and Kenana; n = 52) distributed across six regions of Sudan. Nucleotide sequences were genotyped using the sequence-based typing method. We describe 53 alleles, including seven novel alleles. Principal component analysis (PCA) of the protein pockets implicated in the antigen-binding function of the MHC complex revealed that pockets 4 and 9 (respectively) differentiate Kenana-Baggara and Kenana-Butana breeds from other breeds. Venn analysis of Sudanese, Southeast Asian, European and American cattle breeds with 115 alleles showed 14 were unique to Sudanese breeds. Gene frequency distributions of Baggara cattle showed an even distribution suggesting balancing selection, while the selection index (ω) revealed the presence of diversifying selection in several amino acid sites along the BoLA-DRB3 exon 2 of these native breeds. The results of several PCA were in agreement with clustering patterns observed on the neighbor joining (NJ) trees. These results provide insight into their high survival rate for different tropical diseases and their reproductive capacity in Sudan's harsh environment.
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Bovinos/genética , Haplótipos , Antígenos de Histocompatibilidade Classe II/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Animais , Bovinos/classificação , Evolução Molecular , SudãoRESUMO
Ticks transmit many pathogens with public health and veterinary importance. Despite the wide distribution of tick-borne pathogens in Sudan, the information on the tick-pathogen relationship needs to be updated, particularly using modern molecular techniques. This cross-sectional study, conducted between September and November 2019, used morphology, PCR, and sequencing to confirm the identity of adult cattle ticks (male and female; n = 536) from Khartoum State (n = 417) and East Darfur State (n = 119). Moreover, the presence of Theileria annulata, Babesia bigemina, B. bovis, Anaplasma marginale, and Ehrlichia ruminantium was detected and confirmed in each tick using species-specific PCR or nested PCR and sequencing. The most economically important tick genera, Rhipicephalus, Hyalomma, and Amblyomma, were prevalent in the study area, and 13 different tick species were identified. The most prevalent tick species were Rhipicephalusevertsi evertsi (34.3%) and Hyalomma anatolicum (57.3%) in Khartoum State, and Rhipicephalus annulatus (27%), Rhipicephalus decoloratus (25%), and Hyalomma rufipes (29%) in East Darfur State. We detected all five pathogens in both states. To the best of our knowledge, this is the first study to report the presence of E. ruminantium, its vector Amblyomma variegatum, and B. bovis in Khartoum State. Further, this is the first report on most tick and pathogen species identified in East Darfur State. Our findings indicate the migration of some tick and pathogen species beyond their distribution areas in the country, and this consideration is necessary to develop future control strategies.
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Dromedary camels (Camelus dromedarius) are widely distributed in Africa, the Middle East and northern India. In this study, we aimed to detect tick-borne pathogens through investigating prokaryotic and eukaryotic microorganisms in camel blood based on a metagenomic approach and then to characterize potentially pathogenic organisms using traditional molecular techniques. We showed that the bacteria circulating in the blood of camels is dominated by Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. At the genus level, Sediminibacterium, Hydrotalea, Bradyrhizobium and Anaplasma were the most abundant taxa. Eukaryotic profile was dominated by Fungi, Charophyta and Apicomplexa. At the genus level, Theileria was detected in 10 out of 18 samples, while Sarcocystis, Hoplorhynchus and Stylocephalus were detected in one sample each. Our metagenomic approach was successful in the detection of several pathogens or potential pathogens including Anaplasma sp., Theileria ovis, Th. separata, Th. annulate, Th. mutans-like and uncharacterized Theileria sp. For further characterization, we provided the partial sequences of citrate synthase (gltA) and heat-shock protein (groEL) genes of Candidatus Anaplasma camelii. We also detected Trypanosoma evansi type A using polymerase chain reaction (PCR) targeting the internal transcribed spacer 1 (ITS1) region. This combined metagenomic and traditional approach will contribute to a better understanding of the epidemiology of pathogens including tick-borne bacteria and protozoa in animals.
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Cattle pastoralism plays a central role in human livelihood in Africa. However, the genetic history of its success remains unknown. Here, through whole-genome sequence analysis of 172 indigenous African cattle from 16 breeds representative of the main cattle groups, we identify a major taurine × indicine cattle admixture event dated to circa 750-1,050 yr ago, which has shaped the genome of today's cattle in the Horn of Africa. We identify 16 loci linked to African environmental adaptations across crossbred animals showing an excess of taurine or indicine ancestry. These include immune-, heat-tolerance- and reproduction-related genes. Moreover, we identify one highly divergent locus in African taurine cattle, which is putatively linked to trypanotolerance and present in crossbred cattle living in trypanosomosis-infested areas. Our findings indicate that a combination of past taurine and recent indicine admixture-derived genetic resources is at the root of the present success of African pastoralism.
Assuntos
Adaptação Fisiológica/genética , Cruzamento , Bovinos , Genoma , Sequenciamento Completo do Genoma , África , Alelos , Animais , Bovinos/genética , Genótipo , Temperatura Alta/efeitos adversos , Mosaicismo , Polimorfismo de Nucleotídeo Único , Reprodução/genética , Sequenciamento Completo do Genoma/veterináriaRESUMO
East Coast fever (ECF) is an acute fatal tick-borne disease of cattle caused by Theileria parva. It causes major losses in exotic and crossbreed cattle, but this could be prevented by a vaccine of T. parva if the vaccine is selected properly based on information from molecular epidemiology studies. The Muguga cocktail (MC) vaccine (Muguga, Kiambu 5 and Serengeti-transformed strains) has been used on exotic and crossbreed cattle. A total of 254 T. parva samples from vaccinated and unvaccinated cattle were used to understand the genetic diversity of T. parva in Malawi using partial sequences of the Tp1 and Tp2 genes encoding T. parva CD8+ antigens, known to be immunodominant and current candidate antigens for a subunit vaccine. Single nucleotide polymorphisms were observed at 14 positions (3.65%) in Tp1 and 156 positions (33.12%) in Tp2, plus short deletions in Tp1, resulting in 6 and 10 amino acid variants in the Tp1 and Tp2 genes, respectively. Most sequences were either identical or similar to T. parva Muguga and Kiambu 5 strains. This may suggest the possible expansion of vaccine components into unvaccinated cattle, or that a very similar genotype already existed in Malawi. This study provides information that support the use of MC to control ECF in Malawi.
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The tick-borne parasite Theileria annulata is the causative agent of tropical theileriosis or Mediterranean theileriosis. Infection of bovine leukocytes by the obligate intracellular parasites induces proliferative and invasive phenotypes associated with activated signaling pathways. The transformed phenotypes of infected cells are reversible by treatment with the theilericidal drug buparvaquone. Recent reports of resistance to buparvaquone in Africa and Asia highlight the need to investigate the mechanisms and prevalence of drug resistance. We screened 67 T. annulata isolates from Sudan to investigate mutations in the T. annulata prolyl isomerase I gene (TaPIN1). The secreted TaPin1 interacts with host proteins to induce pathways driving oncogenic transformation and metabolic reprogramming. We found an Alanine-to-Proline mutation at position 53 (A53P) in the catalytic loop that was previously found in Tunisian drug-resistant samples. This is the first study reporting independent confirmation of the A53P mutation in geographically isolated samples. We found several additional mutations in the predicted N-terminal signal peptide that might affect TaPin1 processing or targeting. We found that many parasites also share mutations in both the TaPIN1 and the cytochrome b genes, suggesting that these two genes represent important biomarkers to follow the spread of resistance in Africa, the Middle East and Asia.
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Resistência a Medicamentos/genética , Peptidilprolil Isomerase/genética , Mutação Puntual , Theileria annulata/enzimologia , Theileria annulata/genética , Animais , Antiprotozoários/farmacologia , Bovinos , Naftoquinonas/farmacologia , Fenótipo , Sudão , Theileria annulata/efeitos dos fármacos , Theileriose/parasitologiaRESUMO
This study was carried out to evaluate the application of CATT/T. evansi, crude and recombinant (TeGM6-4r) antigen ELISAs in the diagnosis of camel trypanosomosis caused by two trypanosome species, T. evansi and T. vivax, in Sudan. Concurrently, the current situation of camel trypanosomosis was investigated based on the results of a serological analysis. The recombinant tandem repeat antigen TeGM6-4r is conserved among salivarian trypanosome species and was highly sensitive in the detection Trypanozoon, and T. vivax. It has been validated in the diagnosis of surra in cattle and water buffalo but not in camels. A comparative evaluation of a crude antigen ELISA and a recombinant antigen GM6 (rTeGM6-4r) ELISA was performed using 189 blood samples, which included 148 samples obtained from different camel herds in Eastern Sudan and 41 samples from camels that had been brought from Western Sudan to local markets. The results showed that the rTeGM6-4r ELISA detected the greatest number of positive samples (nâ¯=â¯118, 62%), while CATT/T. evansi and the crude antigen ELISA detected the lowest number of positive samples (nâ¯=â¯73, 39%). The kappa value of rTeGM6-4r as compared to TeCA ELISA was 0.5515, which indicated moderate agreement. We concluded that the rTeGM6-4r ELISA is the test of choice for use in screening camel for trypanosomosis caused by T. evansi and T. vivax in Sudan.