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1.
Rhinology ; 60(6): 479-480, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36150157

RESUMO

Nasal disorders and cardiovascular damage: flow-mediated dilation and intima-media thickness as risk parameters.


Assuntos
Espessura Intima-Media Carotídea , Doenças Nasais , Humanos , Dilatação , Fatores de Risco
2.
Bull Entomol Res ; 110(1): 77-83, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31190645

RESUMO

Flower and leaf herbivory might cause relevant and negative impacts on plant fitness. While flower removal or damage by florivores produces direct negative effects on plant fitness, folivores affect plant fitness by reducing resource allocation to reproduction. In this study, we examine the effects of both flower and leaf herbivory by leaf-cutting ants on the reproductive success of the shrub species Miconia nervosa (Smith) Triana (Family Melastomataceae) in a fragment of Atlantic Forest in Northeast Brazil. We conducted a randomized block-designed field experiment with nine replicates (blocks), in which three plants per block were assigned to one of the three following treatments: undamaged plants (ant exclusion), leaf-damaged plants (ant exclusion from reproductive organs, but not from leaves), and flower + leaf-damaged plants (no exclusion of ants). We then measured flower production, fruit set, and fruit production. Our results showed that flower + leaf-damaged plants reduced flower production nearly twofold in relation to undamaged plants, while flower set in leaf-damaged plants remained constant. The number of flowers that turned into fruits (i.e., fruit set), however, increased by 15% in flower + leaf-damaged plants, while it slightly decreased in leaf-damaged compared to undamaged plants. Contrastingly, fruit production was similar between all treatments. Taken together, our results suggest a prominent role of ant floral herbivory across different stages of the reproductive cycle in M. nervosa, with no consequences on final fruit production. The tolerance of M. nervosa to leaf-cutting ant herbivory might explain its high abundance in human-modified landscapes where leaf-cutting ants are hyper-abundant.


Assuntos
Formigas , Flores/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Herbivoria , Melastomataceae/fisiologia , Animais , Reprodução
3.
Clin Exp Allergy ; 46(6): 785-92, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27009397

RESUMO

Nasal cytology is a simple and safe diagnostic procedure that allows to assess the normal and pathological aspects of the nasal mucosa, by identifying and counting the cell types and their morphology. It can be easily performed by a nasal scraping followed by May-Grunwald-Giemsa staining and optical microscopy reading. This procedure allows to identify the normal cells (ciliated and mucinous), the inflammatory cells (lymphocytes, neutrophils, eosinophils, mast cells), bacteria, or fungal hyphae/spores. Apart from the normal cell population, some specific cytological patterns can be of help in discriminating among various diseases. Viral infections, allergic rhinitis, vasomotor rhinitis and overlapping forms can be easily identified. According to the predominant cell type, various entities can be defined (named as NARES, NARESMA, NARMA). This implies a more detailed knowledge and assessment of the disease that can integrate the standard diagnostic procedures. Nasal cytology also represents a useful research tool for diagnosis and therapy.


Assuntos
Citodiagnóstico , Mucosa Nasal/patologia , Doenças Nasais/diagnóstico , Citodiagnóstico/métodos , Citodiagnóstico/tendências , Diagnóstico Diferencial , Humanos , Doenças Nasais/etiologia
4.
Anim Genet ; 46(2): 122-32, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25643727

RESUMO

Mycobacterium avium subspecies paratuberculosis (MAP) is a pathogenic bacterium responsible for the lethal Johne's disease in cattle. So far, several genome-wide association studies (GWAS) have been carried out to identify chromosomal regions highly associated with Johne's disease. The aim of this study was to investigate the genetic variability within a pool of seven genes (LAMB1, DLD, WNT2, PRDM1, SOCS5, PTGER4 and IL10) indicated by former GWAS/RNA-Seq studies as putatively associated with MAP infections and to achieve a confirmation study of association with paratuberculosis susceptibility in a population of 324 German Holstein cattle (162 cases MAP positive and 162 controls MAP negative) using ELISA and fecal cultural tests. SNP validation and genotyping information are provided, quick methods for allelic discrimination were set up and transcription factor binding analyses were performed. The rs43390642:G>TSNP in the WNT2 promoter region is associated with paratuberculosis susceptibility (P = 0.013), suggesting a protective role of the T allele (P = 0.043; odds ratio 0.50 [0.25-0.97]). The linkage disequilibrium with the DLD rs134692583:A>T might suggest a combined mechanism of action of these neighboring genes in resistance to MAP infection, which is also supported by a significant effect shown by the haplotype DLD(T) /WNT2(T) (P = 0.047). In silico analysis predicted rs43390642:G>T and rs134692583:A>T as essential parts of binding sites for the transcription factors GR, C/EBPß and GATA-1, hence suggesting a potential influence on WNT2 and DLD gene expression. This study confirmed the region on BTA 4 (UMD 3.1: 50639460-51397892) as involved in tolerance/resistance to Johne's disease. In addition, this study clarifies the involvement of the investigated genes in MAP infection and contributes to the understanding of genetic variability involved in Johne's disease susceptibility.


Assuntos
Formação de Anticorpos , Doenças dos Bovinos/genética , Bovinos/genética , Paratuberculose/genética , Animais , Sítios de Ligação/genética , Bovinos/microbiologia , Doenças dos Bovinos/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/imunologia , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/metabolismo
5.
Cytogenet Genome Res ; 139(1): 17-21, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22986410

RESUMO

In recent years increasing attention has been paid to the cytogenetic control of Italian Mediterranean river buffalo (BBU) bulls authorized as sires which are registered in the stud book. Chromosome abnormalities described in this species are mainly numerical and affecting sex chromosomes. During routine cytogenetic analyses performed on young Italian Mediterranean river buffalo bulls in the progeny test, 1 animal was found to be carrier of a never before reported translocation t(1p;18) originated by fission of BBU1 and subsequent centric fusion of BBU1p with BBU18 as demonstrated by both R-banding and FISH-mapping techniques using specific molecular markers of BBU1p (DEFB1) and BBU18 (GPI). According to sperm analyses the semen characteristics were in physiological ranges, but the calf crop percentage was only 48.77% instead of 70-80%. Cytogenetic analyses performed on 50 offspring (36 females and 14 males) showed that 15 of them (30%) were carriers of the same translocation.


Assuntos
Búfalos/genética , Infertilidade Masculina/veterinária , Translocação Genética , Cariótipo Anormal , Animais , Cruzamento , Bandeamento Cromossômico , Cromossomos de Mamíferos/genética , Feminino , Testes Genéticos , Heterozigoto , Hibridização in Situ Fluorescente , Infertilidade Masculina/genética , Masculino
6.
Cytogenet Genome Res ; 139(2): 97-101, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23328281

RESUMO

Reciprocal translocations represent one of the most common structural chromosomal rearrangements observed in both humans and domestic animals. In these translocations, the balanced forms are most frequent but may remain undetected because the carriers show a normal phenotype. For this reason, routine cytogenetic analysis of domestic animals should necessarily rely on banded karyotypes. In fact, during a screening analysis, carried out on phenotypically normal young sheep (Ovis aries, OAR, 2n = 54) from Laticauda-Comisana hybrids, a new structural rearrangement was detected. Two abnormal acrocentric chromosomes (the smallest and the largest one) were found in all metaphases of this carrier animal, suggesting the presence of a reciprocal translocation (rcp). CBA and RBA banding were performed in order to characterize the translocation, and FISH with chromosome-specific BAC probes and telomere probes was applied to confirm the cytogenetic data. The translocation was classified as rcp(4q;12q)(q13;q25).


Assuntos
Cromossomos de Mamíferos/genética , Análise Citogenética/métodos , Carneiro Doméstico/genética , Translocação Genética , Animais , Bandeamento Cromossômico/métodos , Sondas de DNA/genética , Feminino , Hibridização Genética , Hibridização in Situ Fluorescente/métodos , Cariótipo , Cariotipagem/métodos , Masculino , Fenótipo , Reprodutibilidade dos Testes
7.
Cytogenet Genome Res ; 140(1): 29-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23652984

RESUMO

The recent advances in sequencing technology and bioinformatics have revolutionized genomic research, making the decoding of the genome an easier task. Genome sequences are currently available for many species, including cattle, sheep and river buffalo. The available reference genomes are very accurate, and they represent the best possible order of loci at this time. In cattle, despite the great accuracy achieved, a part of the genome has been sequenced but not yet assembled: these genome fragments are called unmapped fragments. In the present study, 20 unmapped fragments belonging to the Btau_4.0 reference genome have been mapped by FISH in cattle (Bos taurus, 2n = 60), sheep (Ovis aries, 2n = 54) and river buffalo (Bubalus bubalis, 2n = 50). Our results confirm the accuracy of the available reference genome, though there are some discrepancies between the expected localization and the observed localization. Moreover, the available data in the literature regarding genomic homologies between cattle, sheep and river buffalo are confirmed. Finally, the results presented here suggest that FISH was, and still is, a useful technology to validate the data produced by genome sequencing programs.


Assuntos
Búfalos/genética , Bovinos/genética , Cromossomos de Mamíferos/genética , Mapeamento Físico do Cromossomo/métodos , Ovinos/genética , Animais , Sequência de Bases , Cromossomos Artificiais Bacterianos/genética , Bases de Dados Genéticas , Loci Gênicos , Genoma , Hibridização in Situ Fluorescente , Subunidade alfa2 de Receptor de Interleucina-13/genética , Reprodutibilidade dos Testes , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
8.
Cytogenet Genome Res ; 133(1): 16-24, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21282943

RESUMO

Cytogenetic maps are useful tools for several applications, such as the physical anchoring of linkage and RH maps or genome sequence contigs to specific chromosome regions or the analysis of chromosome rearrangements. Recently, a detailed RH map was reported in OAR1. In the present study, we selected 38 markers equally distributed in this RH map for identification of ovine genomic DNA clones within the ovine BAC library CHORI-243 using the virtual sheep genome browser and performed FISH mapping for both comparison of OAR1 and homoeologous chromosomes BBU1q-BBU6 and BTA1-BTA3 and considerably extending the cytogenetic maps of the involved species-specific chromosomes. Comparison of the resulting maps with human-identified homology with HSA2q, HSA3, HSA21 and HSA1q reveals complex chromosome rearrangements differentiating human and bovid chromosomes. In addition, we identified 2 new small human segments from HSA2q and HSA3q conserved in the telomeric regions of OAR1p and homoeologous chromosome regions of BTA3 and BBU6, and OAR1q, respectively. Evaluation of the present OAR1 cytogenetic map and the OAR1 RH map supports previous RH assignments with 2 main exceptions. The 2 loci BMS4011 and CL638002 occupy inverted positions in these 2 maps.


Assuntos
Búfalos/genética , Bovinos/genética , Cromossomos Humanos , Cromossomos de Mamíferos , Ovinos/genética , Animais , Células Cultivadas , Análise Citogenética , Humanos , Hibridização in Situ Fluorescente , Mapeamento de Híbridos Radioativos
9.
Cytogenet Genome Res ; 134(2): 96-100, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21389692

RESUMO

A new and unusual reciprocal translocation was detected in a heifer of the Agerolese cattle breed during a routine cytogenetic screening carried out on 13 animals (2 males and 11 females) kept at the ConSDABI Conservation Center in Benevento (Southern Italy). The 13 animals investigated had a normal karyotype except for a 1-year-old female, which carried one autosome smaller than the smallest normal bovine autosomes. This small autosome showed very little C-banding in comparison to the other autosomes, while another medium-sized autosome showed 2 distinct and prominent C-bands. RBA-banding and karyotype analysis revealed that these 2 chromosomes were the result of a reciprocal translocation between chromosomes 11 and 25. FISH analysis with BAC142G06 mapping to the proximal (subcentromeric) region of both BTA25 and der11, BAC513H08 (ELN) mapping to BTA25q22dist and der25, and BAC533C11 mapping to the proximal region of BTA11 and der11 confirmed the localization of the breakpoints on band q11 (centromere) of chromosome 11 and q14-21 of chromosome 25. Ag-NOR and sequential RBA/Ag-NOR techniques detected the presence of NORs on both BTA11 and BTA25 and both der11 and der25. To our knowledge, this is the first report of a reciprocal translocation event in cattle with the breakpoint located in the centromeric region.


Assuntos
Bovinos/genética , Cromossomos de Mamíferos , Translocação Genética , Animais , Células Cultivadas , Centrômero/genética , Feminino , Masculino
10.
Cytogenet Genome Res ; 132(1-2): 26-30, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20693780

RESUMO

A 5-year-old river buffalo cow underwent cytogenetic investigation since it had only one male offspring, apparently with normal body constitution, which died one month after birth. The female carrier had normal body conformation and internal sex adducts, as revealed by rectal palpation performed by a specialist veterinary practitioner. The cow was found to carry a complex and rare chromosome abnormality. Indeed, a centric fission of one river buffalo (BBU) chromosome 1 with a subsequent (or simultaneous) centric fusion of BBU1p with BBU23 was revealed by both RBA-banding and specific molecular markers of BBU1p (DEFB1) and BBU23 (ACTA2). CBA-banding revealed a pale, very small C-band in the der1 (BBU1q) and a prominent C-band on the new biarmed chromosome originated by rob(1p;23). Both telomeric probes and AgNOR staining confirmed the Robertsonian translocation (rob), both FITC-signals and the NORs (BBU23) being telomerically located. Furthermore, telomeric signals on der1 (BBU1q) indicate that these 2 chromosomal events may be the result of a reciprocal translocation which occurred between BBU1 and BBU23.


Assuntos
Búfalos/genética , Infertilidade Feminina/genética , Animais , Bovinos , Bandeamento Cromossômico , Feminino , Hibridização in Situ Fluorescente , Cariotipagem
11.
Mutagenesis ; 26(2): 269-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20952519

RESUMO

In this study, we compared cross-bred dairy cows in the Susa Valley (Piedmont, northern Italy), reared either near a high-temperature steel production plant (Farms A and B) or in an industry-free area (control). Exposed cows (n = 36) were selected based on mean bulk milk toxic equivalent values of polychlorodibenzodioxins (PCDDs) and dioxin-like (DL) polychlorobiphenyls (PCBs) and polychlorodibenzofurans (PCDFs) equal to 18.56 pg/g fat and 8.56 pg/g of fat in dairy cows from Farms A and B, respectively, exceeding both those permitted by the legislation in force (6 pg/g fat PCDDs and DL-PCDFs/PCBs), and those measured in dairy cows (n = 19) of the farm used as control (1.75 pg/g of fat PCDDs and DL-PCDFs/PCBs). Two types of peripheral blood cell cultures were performed: without (normal cultures for the chromosome abnormality (CA)-test: gaps, chromatid breaks, chromosome breaks and fragments) and with addition of bromodeoxyuridine [for the sister chromatid exchange (SCE)-test]. Both tests revealed a significant (P ≤ 0.05) higher chromosome fragility in the exposed cattle compared to controls: CA/cell mean values (without gaps) were 0.65 ± 0.91, 0.51 ± 0.81 and 0.13 ± 0.39 in Farms A, B and controls, respectively, while SCE/cell mean values were 7.00 ± 2.88, 6.39 ± 2.80 and 5.29 ± 2.51. Although the role of other pollutants (e.g. heavy metals) in the genesis of the recorded chromosome alterations cannot be ruled out, our results confirm the findings of previous research into dioxin-exposed sheep.


Assuntos
Benzofuranos/toxicidade , Fragilidade Cromossômica/efeitos dos fármacos , Dioxinas/toxicidade , Poluentes Ambientais/toxicidade , Mutagênicos/toxicidade , Bifenilos Policlorados/toxicidade , Polímeros/toxicidade , Animais , Bovinos , Células Cultivadas , Quebra Cromossômica/efeitos dos fármacos , Cariotipagem , Leite/química , Troca de Cromátide Irmã/efeitos dos fármacos
12.
Neotrop Entomol ; 49(6): 812-820, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32860613

RESUMO

In general, insect herbivore diversity is positively correlated to plant diversity since plant assemblages structure different microhabitats and provide food resources for such insects. Although poorly studied, insect herbivores in tropical dry forests are positively affected by tree species richness and the structural architecture of vegetation. In this study, we analyzed whether true weevil and woody plants present similar patterns of diversity across different landscape units in a Neotropical tropical dry forests located in Brazil, and if there is a correlation among their assemblages. We used Hill numbers according to species richness and the inverse of Simpson to compare the taxonomic diversity of true weevils and plants in nine landscape units located at the São Francisco river basin in the states of Sergipe and Alagoas, north-eastern Brazil. All trees and shrubs with diameter at breast height (1.3 m) ≥ 5 cm were sampled, and true weevils were collected using a modified Malaise trap. We used co-correspondence analysis to test if plants and true weevil species tend to co-occur. A total of 538 true weevils from 60 species was collected, and a total of 1419 plants belonging to 49 species was recorded. There is no general pattern of co-occurrence and diversity among true weevils and plants, indicating that the plant community is not structuring true weevil assemblage in the Caatinga. However, there was positive relationship between Sibinia sp4 and Fabaceae-Mimosoideae. These results suggest true weevil-plant relationships in the Caatinga differ from that of more mesic ecosystems. Therefore, we observed that the mechanisms that regulate herbivore-plant diversity relationships do not always follow a positive relationship, as observed in previous studies.


Assuntos
Biodiversidade , Herbivoria , Gorgulhos , Animais , Brasil , Florestas , Árvores/classificação , Gorgulhos/classificação , Madeira
13.
Cytogenet Genome Res ; 126(1-2): 49-62, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20016156

RESUMO

The present review summarizes the basic cytogenetic information available pertaining to the most important Bovidae species, namely cattle, buffalo, sheep and goat, with the aim of tracing their evolutionary relationships and to provide - for the first time - the hypothetical ancestral karyotype of the Bovinae-Caprinae subfamilies, also in relation to the other nondomestic species which are included in this important taxonomic family. Evolution of the Bovinae-Caprinae autosomes and gonosomes is discussed on the basis of the most recent advances in chromosome banding, linkage studies, FISH-mapping and molecular information.


Assuntos
Animais Domésticos/genética , Evolução Biológica , Bovinos/genética , Bandeamento Cromossômico , Hibridização in Situ Fluorescente , Animais
14.
Cytogenet Genome Res ; 126(1-2): 77-85, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20016158

RESUMO

Few goat genome analysis projects have been developed in the last 10 years. The aim of this review was to compile and update all available cytogenetic mapping data, according to the last goat chromosome nomenclature, as well as human and cattle whole genome sequences. In particular, human regions homologous to most of the FISH-mapped microsatellites were identified in silico. This new goat cytogenetic map made it possible to refine delineation of conserved segments relative to the human and cattle genomic sequence. These improvements did not lead to detection of major new rearrangements within ruminants but confirmed the good conservation of synteny and the numerous intrachromosomal rearrangements observed between goats and humans.


Assuntos
Mapeamento Cromossômico , Análise Citogenética , Cabras/genética , Animais , Humanos , Hibridização in Situ Fluorescente
15.
Cytogenet Genome Res ; 126(1-2): 110-31, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20016161

RESUMO

The association of abnormal chromosome constitutions and disorders of sex development in domestic animals has been recorded since the beginnings of conventional cytogenetic analysis. Deviated karyotypes consisting of abnormal sex chromosome sets (e.g. aneuploidy) and/or the coexistence of cells with different sex chromosome constitutions (e.g. mosaicism or chimerism) in an individual seem to be the main causes of anomalies of sex determination and sex differentiation. Molecular cytogenetics and genetics have increased our understanding of these pathologies, where human and mouse models have provided a substantial amount of knowledge, leading to the discovery of a number of genes implicated in mammalian sex determination and differentiation. Additionally, other genes, which appeared to be involved in ovary differentiation, have been found by investigations in domestic species such as the goat. In this paper, we present an overview of the biology of mammalian sex development as a scientific background for better understanding the body of knowledge of the clinical cytogenetics of disorders of sex development in domestic animals. An attempt to summarize of what has been described in that particular subject of veterinary medicine for each of the main mammalian domestic species is presented here.


Assuntos
Animais Domésticos/genética , Análise Citogenética , Maturidade Sexual/fisiologia , Animais , Animais Domésticos/fisiologia , Hibridização in Situ Fluorescente
16.
Cytogenet Genome Res ; 124(1): 106-11, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19372676

RESUMO

Synchronized peripheral blood lymphocytes from both river buffalo (BBU) and sheep (OAR) were treated for late incorporation of both BrdU and H-33258 to obtain R-banded preparations to be used for FISH-mapping. Ovine BAC-clones were hybridized for three days on slides pre-exposed to UV light after H-33258 staining. The following loci were mapped: GPR103 (BBU7q13, OAR6q13), TRAM1L1(OAR6q13dist), PPP3CA (BBU7q21, OAR6q15), SNCA (OAR6q17), PPARGC1A(BBU7q23, OAR6q17), UGDH (BBU7q25prox, OAR6q22prox), KDR (BBU7q27, OAR6q22), CNOT6L (BBU7q32prox, OAR6q32prox), NUP54 (BBU7q32, BBU6q32), DMP1 (BBU7q34dist-q36prox, OAR6q34dist-q36prox), QDPR (BBU7q36, OAR6q36). All loci mapped in homoeologous chromosomes and chromosome bands of the two species and their locations are in agreement with the previous RH-mapping performed on BBU7 with some difference in the distal region of BBU7. However, the present cytogenetic map better anchors the RH-map on specific river buffalo chromosome bands. In addition, eleven loci were assigned for the first time in sheep to OAR6, noticeably extending the cytogenetic map on this important chromosome which encodes caseins. Two loci (TRAM1L1 and SNCA) mapped in sheep were unmapped in river buffalo in three different FISH experiments. Comparisons between integrated cytogenetic maps of BBU7/OAR6 (and BTA6) with human chromosome 4 (HSA4) revealed complex chromosome rearrangements differentiating these chromosomes.


Assuntos
Búfalos/genética , Cromossomos Humanos Par 4 , Cromossomos/genética , Mapeamento Físico do Cromossomo , Ovinos/genética , Animais , Animais Domésticos , Bisbenzimidazol/metabolismo , Bromodesoxiuridina/metabolismo , Cromossomos Artificiais Bacterianos , Fluoresceína-5-Isotiocianato/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Hibridização in Situ Fluorescente , Propídio/metabolismo , Raios Ultravioleta
17.
Cytogenet Genome Res ; 126(1-2): 63-76, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20016157

RESUMO

The development of a completely annotated sheep genome sequence is a key need for understanding the phylogenetic relationships and genetic diversity among the many different sheep breeds worldwide and for identifying genes controlling economically and physiologically important traits. The ovine genome sequence assembly will be crucial for developing optimized breeding programs based on highly productive, healthy sheep phenotypes that are adapted to modern breeding and production conditions. Scientists and breeders around the globe have been contributing to this goal by generating genomic and cDNA libraries, performing genome-wide and trait-associated analyses of polymorphism, expression analysis, genome sequencing, and by developing virtual and physical comparative maps. The International Sheep Genomics Consortium (ISGC), an informal network of sheep genomics researchers, is playing a major role in coordinating many of these activities. In addition to serving as an essential tool for monitoring chromosome abnormalities in specific sheep populations, ovine molecular cytogenetics provides physical anchors which link and order genome regions, such as sequence contigs, genes and polymorphic DNA markers to ovine chromosomes. Likewise, molecular cytogenetics can contribute to the process of defining evolutionary breakpoints between related species. The selective expansion of the sheep cytogenetic map, using loci to connect maps and identify chromosome bands, can substantially contribute to improving the quality of the annotated sheep genome sequence and will also accelerate its assembly. Furthermore, identifying major morphological chromosome anomalies and micro-rearrangements, such as gene duplications or deletions, that might occur between different sheep breeds and other Ovis species will also be important to understand the diversity of sheep chromosome structure and its implications for cross-breeding. To date, 566 loci have been assigned to specific chromosome regions in sheep and the new cytogenetic map is presented as part of this review. This review will also summarize the current cytogenomic status of the sheep genome, describe current activities in the sheep cytogenomics research sector, and will discuss the cytogenomics data in context with other major sheep genomics projects.


Assuntos
Ovinos/genética , Animais , Sequência de Bases , Análise Citogenética , Primers do DNA , Hibridização in Situ Fluorescente , Locos de Características Quantitativas
18.
Cytogenet Genome Res ; 126(1-2): 217-25, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20016173

RESUMO

The present study was undertaken to investigate aneuploidy rates in the sperm populations of 2 cattle (Bos taurus) breeds by using dual color fluorescent in situ hybridization (FISH) with Xcen and Y chromosome-specific painting probes, obtained by chromosome microdissection and DOP-PCR. Frozen semen from 10 Italian Friesian and 10 Italian Brown testing bulls was used for the investigation. For each bull, more than 5,000 sperm were analyzed, for a total of 52,586 and 51,342 sperm cells for the 2 breeds, respectively. The present study revealed - in both breeds - a preponderance of the Y-bearing sperm compared to the X-bearing sperm. Within each breed, a statistically significant variation in the various classes of aneuploidy (XX, YY and XY) was found: differences were found in the Friesian breed among the 3 diploidy classes, and in the Brown breed, among the 3 disomy classes (p < 0.05) as well as among the 3 diploidy classes (p < 0.01). However, the 2 breeds did not differ significantly in the overall mean rates of X-Y aneuploidy (disomy + diploidy) which amounts to 0.162% in the Italian Friesian and 0.142% in the Italian Brown. When meiosis I (MI) and II (MII) errors were compared, statistically significant differences (p < 0.01) were found in the disomy classes and in both breeds, whereas the differences between diploidy classes were not significant. Compared to humans, a lower level of aneuploidy has been found in the domestic species analyzed so far. The present study contributes to the establishment of a baseline level of aneuploidy in the sperm populations of 2 cattle breeds which could be used for monitoring future trends of reproductive health, especially in relation to environmental changes and mutagens.


Assuntos
Aneuploidia , Bovinos/genética , Cromossomo X , Cromossomo Y , Animais , Hibridização in Situ Fluorescente , Masculino , Espermatozoides/ultraestrutura
19.
Cytogenet Genome Res ; 125(4): 266-71, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19864889

RESUMO

Donkey chromosomes were earlier characterized separately by C-, G- and R-banding techniques. However, direct comparisons between G- and R-banding patterns have still not been carried out in this species. The present study reports this comparison at the 450-band level by using replication G- and R-banding patterns. Two sets of synchronized lymphocyte cultures were set up to obtain early (GBA+CBA-banding) and late (RBA-banding) BrdU incorporation. Slides were stained with acridine orange and observed under a fluorescence microscope. Reverse GBA+CBA- and RBA-banded karyotypes at the 450-band level were constructed. To verify G- and R-banding patterns in some acrocentric chromosomes, sequential GBA+CBA/Ag-NORs and RBA/Ag-NORs were also performed. The results of CBA-banding patterns obtained in 12 animals from 2 breeds showed a pronounced polymorphism of heterochromatin, especially in EAS1q-prox. Ideogrammatic representations of G- and R-banded karyotypes were constructed using only one common G- and R-banding nomenclature. In the present study both G- and R-banding patterns and relative ideograms are presented as standard karyotype for this species at the 450-band level.


Assuntos
Bandeamento Cromossômico/veterinária , Mapeamento Cromossômico/veterinária , Diploide , Equidae/genética , Cariotipagem/veterinária , Animais , Células Sanguíneas/citologia , Divisão Celular , Células Cultivadas , Centrômero , Feminino , Masculino , Região Organizadora do Nucléolo/genética , Região Organizadora do Nucléolo/metabolismo , Coloração pela Prata
20.
Mutagenesis ; 24(6): 471-4, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19640928

RESUMO

For several years, a genetic disease called transversal hemimelia (TH), also known as congenital amputation, has been spreading in Mediterranean Italian buffalo. TH is characterized by the lack of limb distal structures, normally developing proximally to the malformed limb and being amputated at different points distally. A sample of 13 animals affected by TH was examined using the chromosome aberration (CA) test to better characterize chromosome instability already emerging in a preliminary study where we found a significantly higher difference (P < 0.001) in the mean rate of sister chromatid exchange/cell (8.80 +/- 3.19) performed in 10 malformed animals, when compared with the control (6.61 +/- 2.73). The percentage of aneuploid cells was higher in animals with TH (12.76) than in control animals (7.85). Mean gaps are greater in cells of animals with TH (6.62 +/- 2.38) than those found in the control (2.86 +/- 1.01) and similar results were obtained in chromatid breaks (0.13 +/- 0.31 and 0.07 +/- 0.06, respectively), chromosome breaks (0.11 +/- 0.27 and 0.06 +/- 0.13, respectively) and CAs excluding gaps (0.24 +/- 0.47 and 0.13 +/- 0.18, respectively). All these differences are statistically highly significant (P < 0.001).


Assuntos
Búfalos/genética , Instabilidade Cromossômica , Ectromelia/genética , Ectromelia/veterinária , Troca de Cromátide Irmã/genética , Aneuploidia , Animais , Aberrações Cromossômicas , Extremidades , Feminino , Itália , Masculino , Modelos Genéticos
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