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1.
Trop Anim Health Prod ; 55(6): 413, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37994941

RESUMO

The aim of this study was to evaluate the effect of the polymorphic FecGE allele on reproductive traits in Santa Inês and Morada Nova ewes. The traits evaluated were as follows: total progeny weights at birth (PWB) and weaning (PWW) and progeny survival rates at birth (PSRB) and weaning (PSRW). A total of 389 animals, belonging to two Santa Inês herds and one Morada Nova herd, were genotyped. There was a difference between the averages for all the traits studied regarding type of parturition, herd/breed, genotype/herd, and genotype/type of parturition. For each additional progeny, if the female was FecGE/E, the PWB decreased by 1.02 kg and the PWW by 3.16 kg, also with a 0.04% reduction in PSRB and no change in PSRW. If the female was FecGE/+, the reduction in PWB was 0.24 kg, with an increase in PSRW by 0.11%, but no change in PWW and PSRB. In general, these results demonstrate that FecG+/+ females have a better ability to increase their number of progenies without reducing PWB and PWW (also similar to FecGE/+). Thus, it is suggested that further studies on the association between the traits of interest and candidate genes in sheep should be carried out so that the regions which have the greatest effect on the expression of these traits are actually identified. It was not possible to verify the effect of the FecGE allele on the PWB, PWW, PSRB, and PSRW in these Morada Nova and Santa Inês herds.


Assuntos
Parto , Feminino , Animais , Ovinos/genética , Gravidez , Brasil , Genótipo , Fenótipo , Alelos
2.
J Equine Vet Sci ; 126: 104251, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36796740

RESUMO

Optimization of DNA collection for National gene bank and conservation programs requires information on spatial and genetic distribution of animals countrywide. The relationship between genetic and geographic distances were examined in 8 Brazilian horse breeds (Baixadeiro, Crioulo, Campeiro, Lavradeiro, Marajoara, Mangalarga Marchador, Pantaneiro and Puruca) using Single Nucleotide Polymorphism markers and collection point locations. Mantel correlations, Genetic Landscape Shape Interpolation, Allelic Aggregation Index Analyses and Spatial autocorrelation tests indicated a nonrandom distribution of horses throughout the country. Minimum collection distances for the national Gene Bank should be 530km, with clear divisions seen in genetic structure of horse populations in both North/South and East/West directions. Comparing Pantaneiro and North/Northeastern breeds, physical distance is not necessarily the defining factor for genetic differentiation. This should be considered when sampling these local breeds. These data can help optimise GenBank collection routines and conservation strategies for these breeds.


Assuntos
Variação Genética , Animais , Cavalos/genética , Variação Genética/genética , Brasil
3.
Trop Anim Health Prod ; 54(5): 276, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36070151

RESUMO

The study aimed to verify the influence of the FecGE mutation in superovulated ewes and to evaluate the probability of logistic models to determine the response capacity of these ewes to superovulatory treatment. Santa Inês ewes (n = 29) were genotyped for the FecGE mutation and separated for their genotype group in carriers of the mutant E allele (FecGE/E, FecG+/E) and non-carrier (FecG+/+) alleles. The ewes underwent hormonal treatment for superovulation. Aside from the genotypes, variables included in the statistical model were reproductive status (empty, early lactation, or late lactation), age (> or < 6 years), and number of births (nulliparous, primiparous, multiparous). The carriers of the mutation could be discriminated from the non-carriers based on the number of corpora lutea, rate of frozen embryos, and fecundity. Recovery rate was significantly higher (P < 0.05) in FecGE/E (94.31%) compared to FecG+/E (63.15%) and FecG+/+ (61.90%) (P < 0.05), whereas fecundity rate of FecG+/+ ewes (50.76%) was significantly higher than FecG+/E (18.96%) and FecGE/E (32.53%) (P < 0.05). We determined in this study that the response to superovulation and embryo production can be discriminated between FecGE/E and FecG+/E ewes in relation to the FecG+/+ genotype. Logistic models that included reproductive status and mutation, or reproductive status and age, or reproductive status and number of births were effective in predicting the response to superovulatory treatment.


Assuntos
Embrião de Mamíferos , Superovulação , Animais , Corpo Lúteo , Feminino , Lactação , Modelos Logísticos , Ovinos
4.
Mol Genet Genomics ; 297(2): 449-462, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35150300

RESUMO

Since domestication, horse breeds have adapted to their environments and differentiated from one another. This paper uses two methods to detect selection signatures in 23 horse breeds, eight of which are Brazilian (610 animals), both cold-blooded and warm-blooded, from temperate and tropical regions. These animals were genotyped using the GGP Equine BeadChip and we analysed the data by Principal Component Analysis (PCA). The samples were separated into groups based on their geographical area of origin and PCA results studied. The genomic regions under selection were detected by hapFLK and PCAdapt methodologies, identifying six regions under selection with at least one Brazilian horse breed. These regions contain genes associated with heat tolerance, skin colour, body size, energy production/metabolism, genes involved in protein degradation/turnover/DNA repair, genes reducing the impact of oxidative stress/cellular repair, and transcriptional regulation. This work confirmed LCORL and NCAPG gene regions in previous studies associated with body size on Equine Chromosome Autosome 3 (ECA3). On the same ECA3, a region implicating genes linked to coat colour was identified, also previously related to heat stress. Regions with genes coding heat shock proteins were found on ECA1 and 2, and many candidate genes for oxidation-reduction which are a natural response to heat stress. However, a larger sample size and whole-genome SNPs are needed to understand better and identify new candidate regions as well as their functional relation with heat tolerance.


Assuntos
Termotolerância , Animais , Brasil , Genoma , Genômica/métodos , Genótipo , Cavalos/genética , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética , Termotolerância/genética
5.
Genes (Basel) ; 14(1)2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36672811

RESUMO

Small ruminant lentiviruses (SRLVs) affect sheep and goats worldwide. The major gene related to SRLV infections is the Transmembrane Protein Gene 154 (TMEM154). We estimated the haplotype frequencies of TMEM154 in the USA (USDA-ARS) and Brazil (Embrapa) Gene Banks by using two different SNP genotyping methodologies, FluidigmTM and KASPTM. We also genotyped the ZNF389_ss748775100 deletion variant in Brazilian flocks. A total of 1040 blood samples and 112 semen samples from 15 Brazilian breeds were genotyped with Fluidigm for the SNP ZNF389_ss748775100 and 12 TMEM154 SNPs. A total of 484 blood samples from the Santa Inês breed and 188 semen samples from 14 North American sheep breeds were genotyped with KASP for 6 TMEM154 SNPs. All the Brazilian samples had the "I/I" genotype for the ZNF389_ss748775100 mutation. There were 25 TMEM154 haplotypes distributed across the Brazilian breeds, and 4 haplotypes in the US breeds. Haplotypes associated with susceptibility were present in almost all breeds, which suggests that genetic testing can help to improve herd health and productivity by selecting non-susceptible animals as founders of the next generations. Fluidigm and KASP are reliable assays when compared with Beadchip arrays. Further studies are necessary to understand the unknown role of TMEM154 mutations, host-pathogen interaction and new genes associated with the clinical condition.


Assuntos
Lentivirus , Doenças dos Ovinos , Ovinos/genética , Animais , Lentivirus/genética , Brasil , Doenças dos Ovinos/genética , Mutação , Testes Genéticos
6.
Trop Anim Health Prod ; 53(6): 525, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34709458

RESUMO

Among the animal species first introduced in Brazil during the country's discovery, horses (Equus caballus) stand out because of their evolutionary history and relationship with humans. Among the Brazilian horse breeds, the Pantaneiro draws attention due to its adaptative traits. Blood samples of 116 Pantaneiro horses were divided into six populations based on their sampling location, aiming to identify the existence of genetic structure and quantify genetic diversity within and between them. Populations were compared to elucidate genetic variability and differentiation better and assess the impact of Pantanal's natural geographic barriers on gene flow between populations. Data from the GGP Equine BeadChip (Geneseek-Neogen, 65.157 SNPs) was used to assess basic diversity parameters, genetic distance (FST), principal component analysis (PCA), and population structure (ADMIXTURE) for the sampled animals. Mantel test was also performed to investigate the correlation between the populations' genetic and geographic distances. Results showed high genetic variability in all populations, with elevated levels of admixture in their structure. High levels of admixture make it challenging to establish a racial pattern and, consequently, populations within the breed, being that only one of the populations differentiated itself from the others. No significant correlations between genetic and geographic distances were observed, indicating that environmental barriers did not hinder gene flow between populations, and neither farmers' selection practices might have change breed genetic composition significantly. Low genetic distance and similar heterozygosity values were observed among populations, suggesting strong genetic proximity and low differentiation. Thereby, the Pantaneiro breed does not exhibit genetic subpopulations and could be considered, for conservation purposes, a single big population in the Panatnal region. This study will support sampling strategies for National genebank.


Assuntos
Variação Genética , Genética Populacional , Animais , Brasil , Cavalos/genética , Fenótipo , Polimorfismo de Nucleotídeo Único
7.
Anim Reprod Sci ; 226: 106690, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33561808

RESUMO

This study was conducted to characterize the morphology and morphometry of follicles containing multiple oocytes (MOFs) and determine the association with the FecGE mutation in Santa Inês ewes. Based on the genotypes, 65 ewes were characterized as being homozygous wild-type (n = 25; FecG+/+), heterozygous mutant (n = 27, FecG+/E), and homozygous mutant (n = 13, FecGE/E). The variables evaluated were follicle developmental stage, number of oocytes per follicle, morphology, and morphometry of MOFs. The FecGE mutation did not affect the frequency of MOFs (P > 0.05) (3.0 % in FecG+/+; 3.3 % in FecG+/E; and 3.5 % in FecGE/E). The greater viability (P < 0.05) of MOFs was identified in transitory stage of the FecGE/E (95.0 %) and FecG+/E (90.9 %) when compared to the FecG+/+ genotype (73.3 %). Furthermore, the morphology of transitory follicles with two oocytes was the variable and when evaluated was the most reliable determinant for predicting which ewes had an FecGE mutation. In conclusion, the FecGE mutation did not affect the frequency of MOFs. The ewes with FecGE mutation had a greater frequency of morphologically normal MOFs in the transitory stage. Furthermore, the ewes with the FecGE mutation had a greater likelihood of having MOFs containing two morphologically normal oocytes.


Assuntos
Fator 9 de Diferenciação de Crescimento/genética , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Ovinos/fisiologia , Animais , Feminino , Mutação , Ovinos/genética
8.
Trop Anim Health Prod ; 53(1): 126, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33449218

RESUMO

There are few animal germplasm/gene bank collections in Brazil, and basic studies are needed to attend the future internal and external demands from international partners. The aim of this work was to validate a "proof of concept" that integrates spatial (georeferenced data) and genetic data regarding the local of origin from 3518 DNA samples from 17 different genetic groups or breeds of sheep in the Brazilian Germplasm bank. Spatialisation shows that not all genetic groups have samples in the bank, and collection is concentrated in the conservation nuclei spread nationwide. Only 21% of states with a specific breed have samples in the gene bank. The mean number of animals sampled per collection was 32, while the mean distance travelled to collect samples was 262 km from the conservation nuclei. For example, the Brazilian Somali were only collected in the conservation nucleus in Ceará State. No samples were collected to date for the Cariri breed, which is recognised by the Brazilian Ministry of Agriculture. Only two farms and one breed in the bank are from the northern region. Of the 27 states, there are samples in the gene bank of sheep from 13, so several states have no samples, requiring collection from herds outside the official system of conservation to make sure that studies using this germplasm realised are not biased. Significant genetic differences are seen above 332 km, which should guide future sampling efforts. Suggestions are given for improving the quantity, quality and diversity of samples in the gene bank.


Assuntos
Biodiversidade , Cruzamento , Variação Genética , Ovinos/genética , Agricultura , Animais , Bancos de Espécimes Biológicos , Brasil , Conservação dos Recursos Naturais
10.
Mol Ecol ; 29(6): 1103-1119, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32080922

RESUMO

Invasive alien species are a significant threat to both economic and ecological systems. Identifying the processes that give rise to invasive populations is essential for implementing effective control strategies. We conducted an ancestry analysis of invasive feral swine (Sus scrofa, Linnaeus, 1758), a highly destructive ungulate that is widely distributed throughout the contiguous United States, to describe introduction pathways, sources of newly emergent populations and processes contributing to an ongoing invasion. Comparisons of high-density single nucleotide polymorphism genotypes for 6,566 invasive feral swine to a comprehensive reference set of S. scrofa revealed that the vast majority of feral swine were of mixed ancestry, with dominant genetic associations to Western heritage breeds of domestic pig and European populations of wild boar. Further, the rapid expansion of invasive feral swine over the past 30 years was attributable to secondary introductions from established populations of admixed ancestry as opposed to direct introductions of domestic breeds or wild boar. Spatially widespread genetic associations of invasive feral swine to European wild boar deviated strongly from historical S. scrofa introduction pressure, which was largely restricted to domestic pigs with infrequent, localized wild boar releases. The deviation between historical introduction pressure and contemporary genetic ancestry suggests wild boar-hybridization may contribute to differential fitness in the environment and heightened invasive potential for individuals of admixed domestic pig-wild boar ancestry.


Assuntos
Animais Selvagens/genética , Hibridização Genética , Sus scrofa/genética , Animais , Genética Populacional , Genótipo , Espécies Introduzidas , Polimorfismo de Nucleotídeo Único , Estados Unidos
11.
Anim Reprod Sci ; 208: 106117, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405468

RESUMO

Based on ovarian and follicular variables, there was determination of ewes with different FecGE genotypes. Based on the FecGE genotype, 65 Santa Inês ewes were assigned to three experimental groups: homozygous wild-type (n = 25; FecG+/+), mutant heterozygous (n = 27; FecG+/E) and mutant homozygous (n = 13; FecGE/E). The ewe's ovaries were weighed and measured, then the follicles (oocyte, nucleus and nucleolus) were histologically evaluated for morphometry and morphology. Morphologically normal follicles, in the primordial and transitional stages, explained 70.18% of the variability morphological characteristics between mutant and wild-type ewes. Conducting the morphometric evaluation resulted in a more precise determination of the genotype groups when there was assessment of the primordial and secondary follicular developmental stages. The diameter of the oocyte and the oocyte nucleus of the primordial follicles explained 36.76% of the variability in follicular morphology between ewes with the mutation and those with the wildtype group. Similarly, the core diameter of oocytes in secondary follicles explained 10.63% of the variability in follicular morphology among FecGE/E, FecG+/E and FecG+/+ ewes. Thus, morphologically normal follicles in the primordial and transitional stages of development are the variables that allow for a more precise differentiation of Santa Inês ewes with the FecGE mutation. These variables may be evaluated to make more efficient the adoption of biotechniques that when conducted there is utilisation of follicles in the initial developmental stages as a physiological basis for classifying whether specific follicles are useful when conducting the techniques.


Assuntos
Fertilidade/genética , Folículo Ovariano/fisiologia , Ovinos/fisiologia , Animais , Feminino , Regulação da Expressão Gênica/fisiologia , Genótipo , Ovinos/genética
12.
Sci Rep ; 9(1): 1476, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30728441

RESUMO

Western hemisphere goats have European, African and Central Asian origins, and some local or rare breeds are reported to be adapted to their environments and economically important. By-in-large these genetic resources have not been quantified. Using 50 K SNP genotypes of 244 animals from 12 goat populations in United States, Costa Rica, Brazil and Argentina, we evaluated the genetic diversity, population structure and selective sweeps documenting goat migration to the "New World". Our findings suggest the concept of breed, particularly among "locally adapted" breeds, is not a meaningful way to characterize goat populations. The USA Spanish goats were found to be an important genetic reservoir, sharing genomic composition with the wild ancestor and with specialized breeds (e.g. Angora, Lamancha and Saanen). Results suggest goats in the Americas have substantial genetic diversity to use in selection and promote environmental adaptation or product driven specialization. These findings highlight the importance of maintaining goat conservation programs and suggest an awaiting reservoir of genetic diversity for breeding and research while simultaneously discarding concerns about breed designations.


Assuntos
Cabras/classificação , Cabras/genética , Polimorfismo de Nucleotídeo Único , Adaptação Psicológica , Animais , Argentina , Brasil , Cruzamento , Costa Rica , Genética Populacional , Filogenia , Dinâmica Populacional , Seleção Genética , Estados Unidos
13.
Ecol Evol ; 7(22): 9544-9556, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29187988

RESUMO

Samples of 191 animals from 18 different Brazilian locally adapted swine genetic groups were genotyped using Illumina Porcine SNP60 BeadChip in order to identify selection signatures related to the monthly variation of Brazilian environmental variables. Using BayeScan software, 71 SNP markers were identified as FST outliers and 60 genotypes (58 markers) were found by Samßada software in 371 logistic models correlated with 112 environmental variables. Five markers were identified in both methods, with a Kappa value of 0.073 (95% CI: 0.011-0.134). The frequency of these markers indicated a clear north-south country division that reflects Brazilian environmental differences in temperature, solar radiation, and precipitation. Global spatial territory correlation for environmental variables corroborates this finding (average Moran's I = 0.89, range from 0.55 to 0.97). The distribution of alleles over the territory was not strongly correlated with the breed/genetic groups. These results are congruent with previous mtDNA studies and should be used to direct germplasm collection for the National gene bank.

14.
Genet Mol Biol ; 40(3): 604-609, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28863209

RESUMO

The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups were identified with 33 polymorphic sites. Haplotype diversity (varying from 0.20 to 0.96) and nucleotide diversity (varying from 0.0039 to 0.0239) was lower for locally adapted than for specialized breeds, with the same pattern observed for FST values. Haplogroups identified in Brazilian breeds are in agreement with previous findings in South American samples. The low variability observed mainly in locally adapted breeds, indicates that, to ensure conservation of these breeds, careful reproductive management is needed. Additional genetic characterization studies are required to support accurate decision-making.

15.
Genet. mol. biol ; 40(3): 604-609, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-892429

RESUMO

Abstract The first horses were brought to Brazil by the colonizers after 1534. Over the centuries, these animals evolved and adapted to local environmental conditions usually unsuitable for exotic breeds, thereby originating locally adapted Brazilian breeds. The present work represents the first description of maternal genetic diversity in these horse breeds based on D-loop sequences. A D-Loop HSV-I fragment of 252 bp, from 141 horses belonging to ten Brazilian breeds / genetic groups (locally adapted and specialized breeds) were analysed. Thirty-five different haplotypes belonging to 18 haplogroups were identified with 33 polymorphic sites. Haplotype diversity (varying from 0.20 to 0.96) and nucleotide diversity (varying from 0.0039 to 0.0239) was lower for locally adapted than for specialized breeds, with the same pattern observed for FST values. Haplogroups identified in Brazilian breeds are in agreement with previous findings in South American samples. The low variability observed mainly in locally adapted breeds, indicates that, to ensure conservation of these breeds, careful reproductive management is needed. Additional genetic characterization studies are required to support accurate decision-making.

16.
Genetica ; 145(1): 51-66, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28160169

RESUMO

The cachara (Pseudoplatystoma reticulatum) is a Neotropical freshwater catfish from family Pimelodidae (Siluriformes) native to Brazil. The species is of relative economic importance for local aquaculture production and basic biological information is under development to help boost efforts to domesticate and raise the species in commercial systems. The complete cachara mitochondrial genome was obtained by assembling Illumina RNA-seq data from pooled samples. The full mitogenome was found to be 16,576 bp in length, showing the same basic structure, order, and genetic organization observed in other Pimelodidae, with 13 protein-coding genes, 2 rNA genes, 22 trNAs, and a control region. Observed base composition was 24.63% T, 28.47% C, 31.45% A, and 15.44% G. With the exception of NAD6 and eight tRNAs, all of the observed mitochondrial genes were found to be coded on the H strand. A total of 107 SNPs were identified in P. reticulatum mtDNA, 67 of which were located in coding regions. Of these SNPs, 10 result in amino acid changes. Analysis of the obtained sequence with 94 publicly available full Siluriformes mitogenomes resulted in a phylogenetic tree that generally agreed with available phylogenetic proposals for the order. The first report of the complete Pseudoplatystoma reticulatum mitochondrial genome sequence revealed general gene organization, structure, content, and order similar to most vertebrates. Specific sequence and content features were observed and may have functional attributes which are now available for further investigation.


Assuntos
Peixes-Gato/classificação , Peixes-Gato/genética , Genoma Mitocondrial , Filogenia , Animais , Composição de Bases , Sequência de Bases , Códon , Biologia Computacional/métodos , Genes Mitocondriais , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único
17.
BMC Genomics ; 17: 454, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27297173

RESUMO

BACKGROUND: Copy number variations (CNVs) have been shown to account for substantial portions of observed genomic variation and have been associated with qualitative and quantitative traits and the onset of disease in a number of species. Information from high-resolution studies to detect, characterize and estimate population-specific variant frequencies will facilitate the incorporation of CNVs in genomic studies to identify genes affecting traits of importance. RESULTS: Genome-wide CNVs were detected in high-density single nucleotide polymorphism (SNP) genotyping data from 1,717 Nelore (Bos indicus) cattle, and in NGS data from eight key ancestral bulls. A total of 68,007 and 12,786 distinct CNVs were observed, respectively. Cross-comparisons of results obtained for the eight resequenced animals revealed that 92 % of the CNVs were observed in both datasets, while 62 % of all detected CNVs were observed to overlap with previously validated cattle copy number variant regions (CNVRs). Observed CNVs were used for obtaining breed-specific CNV frequencies and identification of CNVRs, which were subsequently used for gene annotation. A total of 688 of the detected CNVRs were observed to overlap with 286 non-redundant QTLs associated with important production traits in cattle. All of 34 CNVs previously reported to be associated with milk production traits in Holsteins were also observed in Nelore cattle. Comparisons of estimated frequencies of these CNVs in the two breeds revealed 14, 13, 6 and 14 regions in high (>20 %), low (<20 %) and divergent (NEL > HOL, NEL < HOL) frequencies, respectively. CONCLUSIONS: Obtained results significantly enriched the bovine CNV map and enabled the identification of variants that are potentially associated with traits under selection in Nelore cattle, particularly in genome regions harboring QTLs affecting production traits.


Assuntos
Variações do Número de Cópias de DNA , Genoma , Genômica , Locos de Características Quantitativas , Característica Quantitativa Herdável , Animais , Bovinos , Mapeamento Cromossômico , Biologia Computacional/métodos , Estudo de Associação Genômica Ampla , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes
18.
PLoS One ; 10(8): e0136035, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26305794

RESUMO

High density genotyping panels have been used in a wide range of applications. From population genetics to genome-wide association studies, this technology still offers the lowest cost and the most consistent solution for generating SNP data. However, in spite of the application, part of the generated data is always discarded from final datasets based on quality control criteria used to remove unreliable markers. Some discarded data consists of markers that failed to generate genotypes, labeled as missing genotypes. A subset of missing genotypes that occur in the whole population under study may be caused by technical issues but can also be explained by the presence of genomic variations that are in the vicinity of the assayed SNP and that prevent genotyping probes from annealing. The latter case may contain relevant information because these missing genotypes might be used to identify population-specific genomic variants. In order to assess which case is more prevalent, we used Illumina HD Bovine chip genotypes from 1,709 Nelore (Bos indicus) samples. We found 3,200 missing genotypes among the whole population. NGS re-sequencing data from 8 sires were used to verify the presence of genomic variations within their flanking regions in 81.56% of these missing genotypes. Furthermore, we discovered 3,300 novel SNPs/Indels, 31% of which are located in genes that may affect traits of importance for the genetic improvement of cattle production.


Assuntos
Bovinos/genética , Variação Genética , Genoma , Animais , Pareamento de Bases/genética , Cruzamento , Cromossomos de Mamíferos/genética , Ontologia Genética , Marcadores Genéticos , Genótipo , Anotação de Sequência Molecular , Fases de Leitura Aberta/genética , Polimorfismo de Nucleotídeo Único/genética
19.
Biosci. j. (Online) ; 30(6): 1819-1836, nov./dec. 2014. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-948216

RESUMO

A localização de todos os rebanhos de cabras de raça pura no Brasil foi espacializada de acordo com os controles climáticos (Índice de Temperatura e Umidade, precipitação, topografia, umidade relativa do ar) e controles ambientais (altitude, tipo de pastagem). Os dados foram analisados através de uma análise de regressão, variância, logistica e cluster. Matrizes de distância foram construídas de acordo com a longitude/ latitude e os controles ambientais foram correlacionados por meio do teste de Mantel. O ponto médio para a maioria das raças foi encontrado no estado da Bahia, mas no estado de Pernambuco encontraram-se os pontos médias das raças localmente adaptadas. A Anglonubiana foi a raça comercial com o ponto médio mais ao norte, enquanto as raças Toggenburg, Saanen e Alpina tiveram o ponto médio de produção mais ao sul do país. Houve pouca diferença entre os controles ambientais para as raças localamente adaptadas e comerciais, mas raças dupla aptidão encontraram-se nas regiões com menor precipitação e Índice de Desenvolvimento Humano , mas com as temperaturas e área de mata mais elevadas . As raças comerciais são mais difundidas no Brasil do que raças locais, sendo que as últimas ocorrem um maior risco de extinção devido a doenças, seca ou cruzamento com outras raças.


The localization of all flocks of purebred goats in Brazil was spatialized in ARCGIS along with climatic (THI, precipitation, topography, relative humidity) and physical environmental controls (altitude, pasture type). Data were analysed using analysis of variance, logisitic regression and cluster analyses. Distance matrices were constructed using longitude/latitude and those from environmental controls and these were correlated using Mantel test. Midpoint for most breeds was in Bahia State, but in Pernambuco for locally adapted breeds. The Anglonubian was the commercial breed with the northernmost midpoint. Toggenburg, Saanen and Apline breeds had the southernmost midpoint. There was little difference between environmental controls for locally adapted and commercial breeds, but dual purpose breeds were in regions with lower rainfall and HDI but higher temperatures and shrubland. Commercial herds are more widespread in Brazil than local breeds putting the latter at higher risk of extinction through drought, disease or crossing with other breeds.


Assuntos
Temperatura , Ruminantes , Pastagens , Monitoramento Ambiental
20.
Genet Mol Biol ; 37(2): 330-42, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25071397

RESUMO

The identification of regions that have undergone selection is one of the principal goals of theoretical and applied evolutionary genetics. Such studies can also provide information about the evolutionary processes involved in shaping genomes, as well as physical and functional information about genes/genomic regions. Domestication followed by breed formation and selection schemes has allowed the formation of very diverse livestock breeds adapted to a wide variety of environments and with special characteristics. The advances in genomics in the last five years have enabled the development of several methods to detect selection signatures and have resulted in the publication of a considerable number of studies involving livestock species. The aims of this review are to describe the principal effects of natural/artificial selection on livestock genomes, to present the main methods used to detect selection signatures and to discuss some recent results in this area. This review should be useful also to research scientists working with wild animals/non-domesticated species and plant biologists working with breeding and evolutionary biology.

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