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The species Melipona rufiventris Lepeletier, 1836 is a Brazilian native stingless bee that is part of a species complex known as the &lsquo, rufiventris group&rsquo, making it difficult to distinguish between the different species. Populations in this group are facing a severe decline, leading to the risk of local extinction, and therefore, their conservation should be treated as a major concern. This study describes the first set of tri- and tetranucleotide microsatellite markers, using next-generation sequencing technology for use in the identification of genetic diversity and population structure in the &lsquo, A total of 16 microsatellite loci displayed polymorphism. Analysis of the whole data set (n = 50) detected 63 alleles in all loci, ranging from 2 to 7 with a mean of 3.9 alleles/locus. A genetic diversity analysis revealed high values for population differentiation estimates (FST = 0.252, RST = 0.317, and DEST = 0.284) between the Atlantic Forest, Cerrado, and Caatinga biomes. An additional evidence for genetic divergence among populations was also found in the &rsquo, these should be treated as separate conservation units or even as separate species. These microsatellite markers have demonstrated a strong potential for assessing population discrimination in this threatened stingless bee group.

The Santa Ines breed stands out in meat sheep production in Brazil. However, this breed is under risk to lose important traits, especially due to pedigree errors and uncontrolled mating. The use of suitable molecular markers can help in the efficient parentage assignment and kinship analysis. In the present study, we aimed to evaluate the power of different numbers of microsatellite markers in comparison to a genome-wide SNP array in kinship estimation in Santa Ines sheep flocks. Blood samples from 257 animals raised in six flocks located in the Mid-North sub-region of Brazil were used for DNA extraction. The microsatellite data were obtained using four panels with different numbers of loci (10, 12, 15, and 19). The panel OvineSNP50 BeadChip (Illumina Inc.) was used for genotyping the animals with SNP data, which were used to calculate the genomic relationship matrix (G). The COANCESTRY program was used to propose the best kinship estimator among seven that were tested. The R package RELATED was used to obtain kinship estimates. The kinships obtained using SNPs and microsatellites were compared using descriptive analysis and Pearson correlation. It was possible to estimate relatedness between full siblings, half siblings, parent-offspring, and unrelated animals using the four microsatellite panels. However, panels containing less than 15 markers had lower efficiency. Most of the pairs of individuals were unrelated or half sibs. In the six flocks, several pairs of individuals showed some degree of relatedness. This indicates that a great number of related individuals have mated. Our results demonstrated that kinships estimated using microsatellite panels were highly correlated to those obtained using the SNP panel, with correlations above 0.89. Thus, a low number of microsatellite markers estimates kinship in Santa Ines sheep with similar efficiency to a genome-wide SNP panel.

Background. Native meliponines are currently threatened by increased human impacts. The assessment of their genetic variation by microsatellite DNA markers can assist in the conservation of populations and help in the planning and establishment of efficient management strategies. Next generation sequencing has proven to be useful for identifying microsatellite loci from the large amounts of sequence data generated. Methods. The purpose of this study was to develop the first set of microsatellite markers for Melipona fasciculata, selected from partial genome assembly of Illumina paired-end reads. Contigs were created from the resulting paired-end sequence data and these were analyzed with specialized software to extract those reads that contained microsatellite loci. Primer pairs were designed for each detected locus at their flanking regions. Bee samples were genotyped from two different locations for markers characterization and validation. Results. A total of 17 microsatellite loci displayed polymorphism from two different populations of Northeastern Brazil. Mean HE and HO heterozygosities were 0.453 and 0.536, respectively. PIC across all loci ranged from 0.108 to 0.714. A genetic diversity analysis revealed high values for population differentiation estimates (FST = 0.194, RST = 0.230, and Dest = 0.162). PCoA and Bayesian clustering showed a separation of the species into two distinct clusters. Discussion. The Illumina paired-end sequencing system provided a large number of microsatellite loci from the M. fasciculata genome. From the genotyped data this study was able to reveal high FST and RST estimates and suggest the existence of genetic structure. These microsatellite markers have demonstrated strong potential for population-level genetic studies and can be used effectively as a molecular tool. Moreover, the exploratory analysis of the genetic diversity in M. fasciculata provides provisional evidence of significant population differentiation between the two studied populations.

A abelha sem ferrão Melipona subnitida atualmente está presente em quase toda a região nordeste, em função da boa adaptabilidade ao semiárido nordestino e do potencial econômico-ecológico proporcionado pela produção de mel e pela polinização de cultivos em condições de confinamento. Apesar disso, é uma espécie ameaçada devido a processos de degradação ambiental, dentre os quais estão o desmatamento, o uso indiscriminado de agrotóxicos e o extrativismo. Tais interferências tendem a isolar as populações de Jandaíra, provocando uma queda na variabilidade genética e, consequentemente, uma redução na capacidade adaptativa da espécie. Porém, técnicas de biologia molecular estão sendo implementadas, possibilitando que populações desse tipo sejam avaliadas quanto ao seu grau de variabilidade genética. Marcadores moleculares do tipo microssatélites de DNA vêm sendo bastante usados, porém, em função do alto custo exigido para seu desenvolvimento, diversos estudos vêm empregando microssatélites transferidos de táxons próximos com amplo sucesso em estudos voltados à caracterização e à diversidade genética. Dessa forma, a presente revisão objetivou avaliar os mais relevantes aspectos bioecológicos e genético-comportamentais envolvidos na conservação da abelha Jandaíra, a fim de auxiliar na avaliação do grau de diversidade genética da espécie, bem como da sua distribuição entre indivíduos e populações da abelha sem ferrão M. subnitida.

For a snapshot assessment of the genetic diversity present within Melipona subnitida, an endemic stingless bee distributed in the semi-arid region of northeastern Brazil, populations separated by over 1,000 km distance were analyzed by ISSR genotyping. This is a prerequisite for the establishment of efficient management and conservation practices. From 21 ISSR primers tested, only nine revealed consistent and polymorphic bands (loci). PCR reactions resulted in 165 loci, of which 92 were polymorphic (57.5%). Both ΦST (ARLEQUIN) and θB (HICKORY) presented high values of similar magnitude (0.34, p

In poultry, the reduction in genetic variability of native chicken populations has led to the use of microsatellites in many genetic studies of chicken ecotypes. To be of maximum usefulness as a genetic marker, microsatellite primers should be amplifying the same locus other than the source of the primer sequence in different populations. Even in closely related lines or breeds microsatellite genotyping errors may be introduced from primer mismatches as a result of mutations in the primer binding sites. Therefore, the selection, use and optimization of microsatellites are considered to be a fundamental step towards full success in genetic studies. Herein, 20 microsatellite loci are presented with great potential for diversity studies in Brazilian chicken ecotypes. The analyses of these ecotypes revealed a total of 191 robust alleles, ranging from three to 18, with an average of 9.6 alleles per locus. The average observed heterozygosity was 0.785, while the mean expected heterozygosity was 0.688. Additionally, the mean polymorphic information content value (0.731) further reflected high level of polymorphism across all microsatellite loci. The topology of the dendrogram constructed with the neighbour-joining method showed probable patterns of relationship and genetic differentiation among the individual ecotypes. Overall, microsatellite loci have proven to be highly useful for studying the variability of chicken ecotypes in the Mid-North region of Brazil.

Os caprinos (Capra hircus) estão distribuídos mundialmente favorecidos por sua capacidade de se adaptar a condições ambientais adversas. A sua importância socioeconômica, têm recebido atenção em pesquisas com o uso de marcadores genéticos (SNP), que possibilitam esclarecer questões envolvendo mudanças evolutivas e auxiliam na conservação da biodiversidade populacional. Com esta revisão, objetivou-se analisar a contribuição de marcadores SNP em estudos com caprinos, com foco na produção e na conservação genética. Utilizou-se o software de pesquisa bibliométrica Bibexcel para análise das publicações da Web of Science TM, até agosto de 2018, rastreando artigos com marcador genético SNP. Das 53.000 produções científicas registradas para a espécie C. hircus, 390 publicações empregaram os marcadores SNPs. Um total de 59 países apresentou publicações envolvendo o uso de SNPs nessa espécie, sendo a maioria das publicações de países asiáticos e europeus. Os cinco países de maior produtividade em publicações no tópico foram a China, a Índia, a Itália, a Espanha e os EUA. O Brasil apresentou-se na décima primeira posição, com registro de 05 publicações. Várias das palavras-chave foram agrupadas por serem de forma semântica equivalentes e associadas a um tema específico; assim, foi possível identificar 23% das produções científicas associadas ao tema polimorfismo de proteínas lácteas, 23% com aspectos da reprodução, 13% ligadas ao crescimento e ganho de peso; e diversidade genética com percentual de 34%. Estudos de GWAS foram citados em 7% das produções e menos de 1% dos estudos foi associado a características de adaptação. Made available in DSpace on 2020-10-29T18:11:29Z (GMT). No. of bitstreams: 1 AplicacaoMarcadoresSNPCarpaHircusAZ2020.pdf: 472003 bytes, checksum: 7e2bc20577e434ce31496109b3874c1b (MD5) Previous issue date: 2020 Autoria na publicação: SOBRINHO, F. A. D.; SILVA, G. R.; ARAUJO, A. M.

Brazilian native meliponines are currently threatened by increased human impacts. The assessment of their genetic variation by microsatellite DNA markers can assist in the conservation of populations and help in the planning and establishment of effi cient management strategies. The purpose of this study was to develop the fi rst set of microsatellite markers for Melipona fasciculata, selected from partial genome assembly of Illumina paired-end reads. Primer pairs were designed for each detected locus at their fl anking regions. Bee samples were genotyped from two different populations of Northeastern Brazil for marker characterization and validation... Made available in DSpace on 2018-12-05T00:00:23Z (GMT). No. of bitstreams: 1 Genomewidediscoveryandcharacterizationofmicrosatellitemarkers.pdf: 513373 bytes, checksum: 6e2d1114610343a6b47e57202508b2e4 (MD5) Previous issue date: 2018-12-04