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1.
Anim Genet ; 55(4): 527-539, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38716584

RESUMO

The conservation of animal genetic resources refers to measures taken to prevent the loss of genetic diversity in livestock populations, including the protection of breeds from extinction. Creole cattle populations have suffered a drastic reduction in recent decades owing to absorbent crosses or replacement with commercial breeds of European or Indian origin. Genetic characterization can serve as a source of information for conservation strategies to maintain genetic variation. The objective of this work was to evaluate the levels of inbreeding and kinship through the use of genomic information. A total of 903 DNAs from 13 cattle populations from Argentina, Bolivia and Uruguay were genotyped using an SNP panel of 48 K. Also, a dataset of 76 K SNPs from Peruvian Creole was included. Two inbreeding indices (FROH and Fhat2) and kinship relationships were calculated. In addition, effective population size (Ne), linkage disequilibrium, population composition and phylogenetic relationships were estimated. In Creole cattle, FROH ranged from 0.14 to 0.03, and Fhat2 was close to zero. The inferred Ne trends exhibited a decline toward the present for all populations, whereas Creole cattle presented a lower magnitude of Ne than foreign breeds. Cluster analysis clearly differentiated the taurine and Zebu components (K2) and showed that Bolivian Creole cattle presented Zebu gene introgression. Despite the population reduction, Creole populations did not present extreme values of consanguinity and kinship and maintain high levels of genetic diversity. The information obtained in this work may be useful for planning conservation programmes for these valuable local animal genetic resources.


Assuntos
Endogamia , Polimorfismo de Nucleotídeo Único , Animais , Bovinos/genética , Uruguai , Bolívia , Cruzamento , Desequilíbrio de Ligação , Filogenia , Genótipo , Argentina , Linhagem , Variação Genética , Genética Populacional , Densidade Demográfica
2.
Microbiol Spectr ; 12(5): e0004724, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38546218

RESUMO

Surface waters are considered ecological habitats where Salmonella enterica can persist and disseminate to fresh produce production systems. This study aimed to explore the genomic profiles of S. enterica serotypes Typhimurium, Newport, and Infantis from surface waters in Chile, Mexico, and Brazil collected between 2019 and 2022. We analyzed the whole genomes of 106 S. Typhimurium, 161 S. Newport, and 113 S. Infantis isolates. Our phylogenetic analysis exhibited distinct groupings of isolates by their respective countries except for a notable case involving a Chilean S. Newport isolate closely related to two Mexican isolates, showing 4 and 13 single nucleotide polymorphisms of difference, respectively. The patterns of the most frequently detected antimicrobial resistance genes varied across countries and serotypes. A strong correlation existed between integron carriage and genotypic multidrug resistance (MDR) across serotypes in Chile and Mexico (R > 0.90, P < 0.01), while integron(s) were not detected in any of the Brazilian isolates. By contrast, we did not identify any strong correlation between plasmid carriage and genotypic MDR across diverse countries and serotypes.IMPORTANCEUnveiling the genomic landscape of S. enterica in Latin American surface waters is pivotal for ensuring public health. This investigation sheds light on the intricate genomic diversity of S. enterica in surface waters across Chile, Mexico, and Brazil. Our research also addresses critical knowledge gaps, pioneering a comprehensive understanding of surface waters as a reservoir for multidrug-resistant S. enterica. By integrating our understanding of integron carriage as biomarkers into broader MDR control strategies, we can also work toward targeted interventions that mitigate the emergence and dissemination of MDR in S. enterica in surface waters. Given its potential implications for food safety, this study emphasizes the critical need for informed policies and collaborative initiatives to address the risks associated with S. enterica in surface waters.


Assuntos
Farmacorresistência Bacteriana Múltipla , Filogenia , Salmonella enterica , Salmonella typhimurium , Sorogrupo , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Brasil , Farmacorresistência Bacteriana Múltipla/genética , México , Salmonella typhimurium/genética , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/classificação , Integrons/genética , Genoma Bacteriano , Chile , Genômica , Antibacterianos/farmacologia , América Latina , Microbiologia da Água , Polimorfismo de Nucleotídeo Único , Plasmídeos/genética , Testes de Sensibilidade Microbiana
3.
Comput Struct Biotechnol J ; 20: 1821-1828, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35521552

RESUMO

Genetic and omics analyses frequently require independent observations, which is not guaranteed in real datasets. When relatedness cannot be accounted for, solutions involve removing related individuals (or observations) and, consequently, a reduction of available data. We developed a network-based relatedness-pruning method that minimizes dataset reduction while removing unwanted relationships in a dataset. It uses node degree centrality metric to identify highly connected nodes (or individuals) and implements heuristics that approximate the minimal reduction of a dataset to allow its application to complex datasets. When compared with two other popular population genetics methodologies (PLINK and KING), NAToRA shows the best combination of removing all relatives while keeping the largest possible number of individuals in all datasets tested and also, with similar effects on the allele frequency spectrum and Principal Component Analysis than PLINK and KING. NAToRA is freely available, both as a standalone tool that can be easily incorporated as part of a pipeline, and as a graphical web tool that allows visualization of the relatedness networks. NAToRA also accepts a variety of relationship metrics as input, which facilitates its use. We also release a genealogies simulator software used for different tests performed in this study.

4.
Mol Genet Metab Rep ; 30: 100840, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35242572

RESUMO

Lecithin-cholesterol acyltransferase (LCAT), an enzyme that participates in lipoprotein metabolism, plays an important role in cholesterol homeostasis. Mutations in the LCAT gene can cause two rare genetic disorders: familial LCAT deficiency (FLD), which is characterized by corneal opacities, normocytic anemia, dyslipidemia, and proteinuria progressing to chronic renal failure, and fish-eye disease (FED), which causes dyslipidemia and progressive corneal opacities. Herein, we report six suspected cases of FLD in the backlands of Piauí, located in northeast Brazil. A genetic diagnosis was performed in index cases. Among these, a further investigation was performed to identify new cases in the families. In addition, molecular analyses were performed to verify the levels of consanguinity within families and the existence of a genetic relationship between them. All six index cases were confirmed as FLD with an identical mutation (c.803G > A, p.R268H). The genetic investigation confirmed another 7 new cases of FLD, 52 heterozygous and 6 individuals without mutations. The rate of consanguinity revealed that marriages within the family did not contribute to the high number of FLD cases within the restricted region. The elders of each family (patriarchs and matriarchs) were subjected to a kinship analysis and were more genetically related to each other than the control group. Bayesian analysis was implemented to confirm the hypothesis of connectivity among patriarchs and matriarchs and indicated that they were genetically more related to each other than would be randomly expected, thus suggesting the occurrence of a possible founder effect in these families.

5.
Behav Processes ; 193: 104524, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34592345

RESUMO

Third-party interventions may regulate conflicts to reduce aggression and promote cohesion amongst group members, but are rarely documented in ungulates. The white-lipped peccary (Tayassu pecari) lives in mixed-sex herds of hundreds of individuals in Neotropical forests, which are likely to benefit from mechanisms that sustain social cohesiveness. We examined third-party conflict interventions between individuals in captive groups of white-lipped peccaries. During a period of 60 days, we recorded agonistic interactions and occurrences of third-party conflict interventions, and estimated the genetic relatedness between the individuals involved using multilocus microsatellite genotypes. Most third-party conflict interventions were by the dominant male of each group, resulting in conflict termination 100% of the time. Our results also revealed that white-lipped peccaries favour their closest relatives and that individuals showed lower levels of aggression towards kin than to non-kin, and interventions on behalf of kin were more frequent than on behalf of non-kin. Our findings support the idea that genetic relatedness is fundamental in both social structure and third-party conflict interventions in this species, allowing us to suggest that kin selection could have a key role in the evolution of social behaviour of white-lipped peccaries.


Assuntos
Artiodáctilos , Agressão , Animais , Humanos , Masculino , Mamíferos , Comportamento Social
6.
Rev. Inst. Nac. Hig ; 48(1-2): 82-98, 2017. tab, graf
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1000160

RESUMO

En Venezuela, en junio de 1996, se reportó que los casos de cólera eran causados por V. cholerae O1 serotipo Ogawa. A finales de 1998 se detectó un segundo brote de cólera causado por V. cholerae O1 serotipo Inaba resistente a la ampicilina y el trimetoprim-sulfametoxazol. Para estudiar las relaciones entre las cepas se examinaron veinticinco aislados de Vibrio cholerae O1 obtenidos desde 1996 a 2000 en Venezuela, para determinar la presencia de genes de virulencia y perfiles genómicos. Mediante la reacción en cadena de la polimerasa se determinó la presencia de genes de virulencia. Para determinar el perfil genómico de los aislamientos se utilizó ribotipificación y electroforesis en gel de campo pulsado (PFGE). Todos los aislados resultaron positivos para los genes ctxA, ctxB, zot y ace. El análisis RFLP de los genes RNAr mostró un único patrón de ribotipo V. El análisis de PFGE mostró una similitud de 91,5% independientemente del año o lugar de aislamiento, lo que indica la relación genómica entre los aislados. En conjunto, los datos sugieren que la cepa de V. cholerae O1 resistente a los antibióticos que apareció en 1998 surgió de la cepa epidémica anterior o de otro estrechamente relacionado con el clon anterior, con cambio de serotipo y ganancia de determinantes de resistencia a antibióticos. Es muy importante monitorear continuamente la aparición de la variantes porque mejorará la comprensión de la evolución de nuevos clones de V. cholerae


In Venezuela, cholera reported in June 1996 was caused by V. cholerae O1 serotype Ogawa. Second outbreak of cholera caused by V. cholerae O1 serotype Inaba, resistant to ampicillin and trimethoprim- Sulfamethoxazole, was notify at the end of 1998. Twenty-five isolates of Vibrio cholerae O1 obtained from 1996 to 2000 in Venezuela were examined to study the relationships between strains, presence of virulence genes and genomic profiles. Presence of virulence genes was detected by Polymerase Chain Reaction. Ribotyping and pulsed-field gel electrophoresis (PFGE) were used to determine the genomic profile of isolates. All isolates shown PCR product for ctxA, ctxB, zot and ace genes. RFLP analysis of rRNA gene showed one unique pattern from ribotype V. PFGE analysis revealed a similarity of 91.5%, regardless year or place of isolation, suggesting genomic relatedness among them. Overall, these data suggest that antibiotic resistant V. cholerae O1 El Tor strain that appeared in 1998 emerged from the previous epidemic strain or from another closely related to the previous clone. It is important the continuous monitor the emergence of variants because it will improve our understanding of the evolution of new clones V. cholerae


Assuntos
Humanos , Masculino , Feminino , Vibrio cholerae , Cólera/epidemiologia , Ribotipagem , Tipagem Molecular , Vibrio/química , Saúde Pública , Antibacterianos
7.
Primates ; 57(2): 253-65, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26935548

RESUMO

Kinship plays an important role in the social behavior of many primate species, including patterns of intra-group affiliation and cooperation. Within social groups, kinship is strongly affected by dispersal patterns, with the degree of relatedness among group-mates expected to decrease as the tendency to disperse increases. In primate species characterized by bisexual dispersal, relatedness among adult group-mates is predicted to be low, with social interactions shaped largely by factors other than kinship. To date, however, few studies have examined the role of kinship in social interactions in bisexually dispersing species. Accordingly, we collected genetic, spatial and behavioral data on all adult members (three males, six females) in a group of free-ranging mantled howler monkeys (Alouatta palliata)--a bisexually dispersing species of atelid primate--from Barro Colorado Island (BCI), Panama. Analyses of microsatellite variation revealed that relatedness was greater among adult males in this group (mean pairwise relatedness = 0.32 for males versus 0.09 for females). Relatedness among individuals, however, was not associated with either spatial proximity or frequency of social interactions. Instead, sex was a better predictor of both of these aspects of social behavior. While relatedness among adults had no discernible effect on the intra-group social interactions documented in this study, we postulate that kinship may facilitate affiliative and cooperative behaviors among male group-mates when interacting competitively with neighboring howler groups over access to food or potential mates.


Assuntos
Alouatta/fisiologia , Distribuição Animal , Variação Genética , Comportamento Social , Alouatta/genética , Animais , Feminino , Masculino , Repetições de Microssatélites , Panamá
8.
Braz. j. microbiol ; Braz. j. microbiol;47(1): 150-158, Jan.-Mar. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-775101

RESUMO

Abstract Antimicrobial resistance in Escherichia coli isolated from pet dogs can be considered a potential threat of infection for the human population. Our objective was to characterize the resistance pattern, extended spectrum beta-lactamase production and genetic relatedness of multiresistant E. coli strains isolated from dogs (n = 134), their owners (n = 134), and humans who claim to have no contact with dogs (n = 44, control), searching for sharing of strains. The strains were assessed for their genetic relatedness by phylogenetic grouping and pulsed-field gel electrophoresis. Multiresistant E. coli strains were isolated from 42 (31.3%) fecal samples from pairs of dogs and owners, totaling 84 isolates, and from 19 (43.1%) control group subjects. The strains showed high levels of resistance to ampicillin, streptomycin, tetracycline, trimethoprim and sulfamethoxazole regardless of host species or group of origin. The blaTEM, blaCTX-M, and blaSHV genes were detected in similar proportions in all groups. All isolates positive for bla genes were ESBL producers. The phylogenetic group A was the most prevalent, irrespective of the host species. None of the strains belonging to the B2 group contained bla genes. Similar resistance patterns were found for strains from dogs, owners and controls; furthermore, identical PFGE profiles were detected in four (9.5%) isolate pairs from dogs and owners, denoting the sharing of strains. Pet dogs were shown to be a potential household source of multiresistant E. coli strains.


Assuntos
Animais , Cães , Humanos , Farmacorresistência Bacteriana , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Genótipo , beta-Lactamases/genética , Antibacterianos/farmacologia , Eletroforese em Gel de Campo Pulsado , Escherichia coli/genética , Fezes/microbiologia , Tipagem Molecular , Animais de Estimação , Filogenia
9.
Braz J Microbiol ; 47(1): 150-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26887238

RESUMO

Antimicrobial resistance in Escherichia coli isolated from pet dogs can be considered a potential threat of infection for the human population. Our objective was to characterize the resistance pattern, extended spectrum beta-lactamase production and genetic relatedness of multiresistant E. coli strains isolated from dogs (n=134), their owners (n=134), and humans who claim to have no contact with dogs (n=44, control), searching for sharing of strains. The strains were assessed for their genetic relatedness by phylogenetic grouping and pulsed-field gel electrophoresis. Multiresistant E. coli strains were isolated from 42 (31.3%) fecal samples from pairs of dogs and owners, totaling 84 isolates, and from 19 (43.1%) control group subjects. The strains showed high levels of resistance to ampicillin, streptomycin, tetracycline, trimethoprim and sulfamethoxazole regardless of host species or group of origin. The blaTEM, blaCTX-M, and blaSHV genes were detected in similar proportions in all groups. All isolates positive for bla genes were ESBL producers. The phylogenetic group A was the most prevalent, irrespective of the host species. None of the strains belonging to the B2 group contained bla genes. Similar resistance patterns were found for strains from dogs, owners and controls; furthermore, identical PFGE profiles were detected in four (9.5%) isolate pairs from dogs and owners, denoting the sharing of strains. Pet dogs were shown to be a potential household source of multiresistant E. coli strains.


Assuntos
Farmacorresistência Bacteriana , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Genótipo , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Cães , Eletroforese em Gel de Campo Pulsado , Escherichia coli/genética , Fezes/microbiologia , Humanos , Tipagem Molecular , Animais de Estimação , Filogenia
10.
Braz. J. Microbiol. ; 47(1): 150-158, 2016. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-688331

RESUMO

Antimicrobial resistance in Escherichia coli isolated from pet dogs can be considered a potential threat of infection for the human population. Our objective was to characterize the resistance pattern, extended spectrum beta-lactamase production and genetic relatedness of multiresistant E. coli strains isolated from dogs (n = 134), their owners (n = 134), and humans who claim to have no contact with dogs (n = 44, control), searching for sharing of strains. The strains were assessed for their genetic relatedness by phylogenetic grouping and pulsed-field gel electrophoresis. Multiresistant E. coli strains were isolated from 42 (31.3%) fecal samples from pairs of dogs and owners, totaling 84 isolates, and from 19 (43.1%) control group subjects. The strains showed high levels of resistance to ampicillin, streptomycin, tetracycline, trimethoprim and sulfamethoxazole regardless of host species or group of origin. The blaTEM, blaCTX-M, and blaSHV genes were detected in similar proportions in all groups. All isolates positive for bla genes were ESBL producers. The phylogenetic group A was the most prevalent, irrespective of the host species. None of the strains belonging to the B2 group contained bla genes. Similar resistance patterns were found for strains from dogs, owners and controls; furthermore, identical PFGE profiles were detected in four (9.5%) isolate pairs from dogs and owners, denoting the sharing of strains. Pet dogs were shown to be a potential household source of multiresistant E. coli strains. (AU)


Assuntos
Animais , Cães , beta-Lactamases , Escherichia coli , Cães , Filogenia , Distribuição de Qui-Quadrado
11.
J Oral Microbiol ; 12009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21523209

RESUMO

BACKGROUND: It is recognized that Candida dubliniensis commonly colonizes oral and subgingival sites in immunocompetent subjects with periodontal disease. OBJECTIVE: Since there are few data available on genetic characterization of C. dubliniensis in periodontal pockets and other oral sites, the aim of this study was to characterize subgingival and mucosal C. dubliniensis isolates recovered from immunocompetent subjects and to assay the genetic similarity of such isolates from both niches in the same patient by random amplified polymorphic DNA (RAPD). DESIGN: C. dubliniensis recovered from subgingival plaque and from buccal cavity samples were studied in 240 immunocompetent non-smoking individuals. Arbitrary amplification was carried out by RAPD-polymerase chain reaction (PCR). RESULTS: RAPD analysis showed identical genotypes of C. dubliniensis in different sampling sites (buccal cavity and subgingival areas) in eight of 10 patients except for those derived from two participants who presented presumably unrelated isolates. CONCLUSIONS: On the basis of the findings presented, the origin of the colonization of C. dubliniensis in subgingival biofilm seems to be the buccal cavity in a single patient. Consequently, it may be assumed that most of C. dubliniensis in these sites arise from the endogenous commensal strains.

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