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Nomenclatura Unesco > (24) Ciencias de la Vida > (2409) Genética
(2409.01) Embriología (2409.02) Ingeniería genética
(2409.03) Genética de poblaciones (2409.90) Citogenética animal
(2409.91) Genética del desarrollo (2409.92) Genética molecular de plantas
(2409.93) Genética molecular (2409.94) Genética molecular de levaduras
(2409.99) Otras (especificar)

Categorías relacionadas:
(3201.02) Genética clínica (2410.07) Genética humana
(2407.02) Citogenética

Mostrando recursos 1 - 20 de 308,589

1. Comparative electrophoretic patterns of lactase dehydrogenase and malate dehydrogenase in five Lake Victoria cichlid species - Basasibwaki, P.
Biochemical techniques designed to compare species on the basis of protein differences were started by NUTTALL (1904) who used immunological methods to compare the serum of humans with that of other primates. Since then more refined techniques have led to better results at the protein level in taxonomy, The analyses of proteins are considered to be the simplest indirect approach to understanding the structure and function of the genetic material, deoxyribonucleic acid (DNA). Interest in these analyses arises because of the close relationship between protein structure and gene structure. Thus by comparing the properties of homologous proteins from different taxa one...

2. Revisão sistemática e meta-análise do perfil lipídico da carne de bovinos de corte - Canellas, Jéssica Magero
A presente pesquisa objetivou avaliar a influência do sistema de alimentação, região de produção e/ou grupo genético sobre o perfil lipídico da carne de bovinos de corte através de uma sistematização e meta-análise de resultados publicados. Foram utilizados de forma agregada dados de 571 animais provenientes de nove trabalhos. As informações relacionadas à metodologia e aos resultados de cada trabalho foram tabuladas em planilha Microsoft Excel, constituindo a sistematização dos dados. Foi realizada uma meta-análise de subgrupos com co-variáveis qualitativas, modeladas através do software STATA. Os Subgrupos foram organizados da seguinte forma: Região de Produção (RP): América do Sul e...

3. Evolução e diversidade de retrovírus endógenos em felídeos neotropicais - Mata, Helena
Retrovírus endógenos (ERVs) são vírus altamente difundidos no genoma de vertebrados. ERVs surgem quando retrovírus exógenos infectam células germinativas e se disseminam no genoma de seus hospedeiros, transmitindo seu material genético através das gerações por meio de herança mendeliana. ERVs são fundamentais na evolução dos genomas, sendo eles responsáveis por uma parte da diversidade genética de seus hospedeiros. O conhecimento sobre ERVs na família Felidae (Mammalia, Carnivora) estava praticamente restrito ao gato doméstico, e não se conhecia diversidade e padrões de evolução desses retroelementos em outras espécies. Este estudo teve como objetivo investigar diversidade, distribuição e padrões evolutivos de ERVs...

4. Alterações genéticas no gene da iodotironina desiodase tipo 2 e resistencia insulínica - Leiria, Leonardo Barbosa
Introdução. O hormônio tireoidiano na sua forma ativa (T3) possui um importante papel no crescimento, desenvolvimento e no metabolismo dos organismos complexos. A iodotironina desiodase tipo 2 (D2) é uma selenoenzima responsável pela ativação do T3. O polimorfismo de troca única (SNP) Tre92Ala (rs225014) no gene que codifica a D2 foi associado com resistência à insulina em algumas populações; porém, estudos funcionais ex vivo indicaram que esse polimorfismo não seria o fator causal para o desenvolvimento de resistência à insulina. Objetivos. Identificar outras alterações no gene da D2 que pudessem contribuir para o desenvolvimento de resistência à insulina em pacientes...

5. Caracterización fenológica, morfológica, fisiológica, fitoquímica, y molecular de las especies silvestres españolas del género Crocus. - PASTOR FÉRRIZ, MARÍA TERESA
[EN] The genus Crocus belonging to the family Iridaceae, is known for its cultivated species, saffron (Crocus sativus L.). The genus includes about 100 species, many of which are of interest as ornamentals for their products or secondary metabolism, and others are exclusively wild. On the whole, they are a source of genetic variability of enormous interest. The rapid disappearance of the culture of saffron in Europe due to the significant amount of manpower required, has led to significant genetic erosion. In order to slow down and improve this situation, several national and European programs for the collection, multiplication, and characterization...

6. Microsatellite evidence for low genetic diversity and reproductive isolation in tetraploid Centaurea seridis (Asteraceae) coexisting with diploid Centaurea aspera and triploid hybrids in contact zones - Ferriol Molina, María; Merle Farinós, Hugo Basilio; Garmendia, Alfonso
Survival of polyploids in nature depends on several factors, including competition from diploid relatives and increased genetic diversity. Unlike other reported Centaurea polyploid complexes, diploid Centaurea aspera and tetraploid Centaurea seridis coexist in hybrid zones with frequent triploid individuals. The polyploid origin of C. seridis, the genetic diversity and population structure of the three cytotypes, and the degree of genetic differentiation among them were analyzed in seven mixed-ploidy zones, involving different subspecies and ecological conditions. Ploidy was determined by flow cytometry. Microsatellite data suggested an allopolyploid origin of C. seridis. In the contact zones, diploids and tetraploids were genetically differentiated. When compared with the related C. aspera,...

7. The incretin hormone glucagon-like peptide 1 increases mitral cell excitability by decreasing conductance of a voltage-dependent potassium channel. - Thiebaud, N; Llewellyn-Smith, IJ; Gribble, F; Reimann, F; Trapp, S; Fadool, DA
The olfactory system is intricately linked with the endocrine system where it may serve as a detector of internal metabolic state or energy homeostasis in addition to its classical function as a sensor of external olfactory information. The recent development of transgenic mGLU-YFP mice that express a genetic reporter under the control of the preproglucagon reporter, suggested the presence of the gut hormone, glucagon-like peptide (GLP-1) in deep short axon cells (dSAC; Cajal cells) of the olfactory bulb and its neuromodulatory effect on the mitral cell (MC) first order neurons. A MC target for the peptide was determined using GLP-1R...

8. The impact of genetic polymorphisms on the pharmacokinetics of efavirenz in African children. - Bienczak, A; Cook, A; Wiesner, L; Olagunju, A; Mulenga, V; Kityo, C; Kekitiinwa, A; Owen, A; Walker, AS; Gibb, DM; McIlleron, H; Burger, D; Denti, P
AIM: To characterise the efavirenz steady-state pharmacokinetics in African children using model-based approach, quantifying demographic and genotypic effects on the drug's disposition, and conduct simulations allowing prediction of optimised doses of efavirenz in this population. METHODS: We modelled the steady-state population pharmacokinetics of efavirenz in Ugandan and Zambian children using nonlinear mixed-effects modelling. Individual mid-dose efavirenz concentrations were derived and simulations explored genotype-based dose optimisation strategies. RESULTS: A 2-compartment model with absorption through transit compartments well described 2086 concentration-time points in 169 children. The combined effect of SNPs 516GT and 983TC explained 44.5% and 14.7% of the variability in efavirenz...

9. Inferences from tip-calibrated phylogenies: a review and a practical guide. - Rieux, A; Balloux, F
Molecular dating of phylogenetic trees is a growing discipline using sequence data to co-estimate the timing of evolutionary events and rates of molecular evolution. All molecular-dating methods require converting genetic divergence between sequences into absolute time. Historically, this could only be achieved by associating externally derived dates obtained from fossil or biogeographical evidence to internal nodes of the tree. In some cases, notably for fast-evolving genomes such as viruses and some bacteria, the timespan over which samples were collected may cover a significant proportion of the time since they last shared a common ancestor. This situation allows phylogenetic trees to...

10. Glucocerebrosidase in Parkinson's disease: Insights into pathogenesis and prospects for treatment. - Schapira, AH; Chiasserini, D; Beccari, T; Parnetti, L
PD involves several converging pathogenetic pathways to neurodegeneration; highlighted in specific cases by genetic mutations causing familial PD. Numerically, the most important genetic mutations associated with PD are those of the glucocerebrosidase gene. Approximately 10% of PD patients carry glucocerebrosidase mutations. This observation has enhanced focus on the autophagy-lysosome system as important in pathogenesis. The relationship of the glucocerebrosidase pathway to the cause and progression of PD highlights the potential to use abnormalities identified as biomarkers and modify glucocerebrosidase activity or substrate accumulation as neuroprotection. Biomarkers relevant to the glucocerebrosidase pathway, for example, enzyme activity and substrate levels, may be...

11. Assessing the genetic architecture of epithelial ovarian cancer histological subtypes. - Cuellar-Partida, G; Lu, Y; Dixon, SC; Australian Ovarian Cancer Study,; Fasching, PA; Hein, A; Burghaus, S; Beckmann, MW; Lambrechts, D; Van Nieuwenhuysen, E; Vergote, I; Vanderstichele, A; Doherty, JA; Rossing, MA; Chang-Claude, J; Rudolph, A; Wang-Gohrke, S; Goodman, MT; Bogdanova, N; Dörk, T; Dürst, M; Hillemanns, P; Runnebaum, IB; Antonenkova, N; Butzow, R; Leminen, A; Nevanlinna, H; Pelttari, LM; Edwards, RP; Kelley, JL; Modugno, F; Moysich, KB; Ness, RB; Cannioto, R; Høgdall, E; Høgdall, C; Jensen, A; Giles, GG; Bruinsma, F; Kjaer, SK; Hildebrandt, MA; Liang, D; Lu, KH; Wu, X; Bisogna, M; Dao, F; Levine, DA; Cramer, DW; Terry, KL; Tworoger, SS; Stampfer, M; Missmer, S; Bjorge, L; Salvesen, HB; Kopperud, RK; Bischof, K; Aben, KK; Kiemeney, LA; Massuger, LF; Brooks-Wilson, A; Olson, SH; McGuire, V; Rothstein, JH; Sieh, W; Whittemore, AS; Cook, LS; Le, ND; Blake Gilks, C; Gronwald, J; Jakubowska, A; Lubiński, J; Kluz, T; Song, H; Tyrer, JP; Wentzensen, N; Brinton, L; Trabert, B; Lissowska, J; McLaughlin, JR; Narod, SA; Phelan, C; Anton-Culver, H; Ziogas, A; Eccles, D; Campbell, I; Gayther, SA; Gentry-Maharaj, A; Menon, U; Ramus, SJ; Wu, AH; Dansonka-Mieszkowska, A; Kupryjanczyk, J; Timorek, A; Szafron, L; Cunningham, JM; Fridley, BL; Winham, SJ; Bandera, EV; Poole, EM; Morgan, TK; Goode, EL; Schildkraut, JM; Pearce, CL; Berchuck, A; Pharoah, PD; Webb, PM; Chenevix-Trench, G; Risch, HA; MacGregor, S
Epithelial ovarian cancer (EOC) is one of the deadliest common cancers. The five most common types of disease are high-grade and low-grade serous, endometrioid, mucinous and clear cell carcinoma. Each of these subtypes present distinct molecular pathogeneses and sensitivities to treatments. Recent studies show that certain genetic variants confer susceptibility to all subtypes while other variants are subtype-specific. Here, we perform an extensive analysis of the genetic architecture of EOC subtypes. To this end, we used data of 10,014 invasive EOC patients and 21,233 controls from the Ovarian Cancer Association Consortium genotyped in the iCOGS array (211,155 SNPs). We estimate...

12. Body Mass Index and Depressive Symptoms: Testing for Adverse and Protective Associations in Two Twin Cohort Studies. - Jokela, M; Berg, V; Silventoinen, K; Batty, GD; Singh-Manoux, A; Kaprio, J; Davey Smith, G; Kivimäki, M
Studies have suggested both adverse and protective associations of obesity with depressive symptoms. We examined the contribution of environmental and heritable factors in this association. Participants were same-sex twin pairs from two population-based twin cohort studies, the Older Finnish Twin Cohort (n = 8,215; mean age = 44.1) and the US Midlife Development in the United States (MIDUS; n = 1,105; mean age = 45.1). Body mass index (BMI) was calculated from self-reported height and weight. Depressive symptoms were assessed using Beck's Depression Inventory (BDI; Finnish Twin Cohort), and by negative and positive affect scales (MIDUS). In the Finnish Twin...

13. Divergent mitochondrial respiratory chains in phototrophic relatives of apicomplexan parasites. - Flegontov, P; Michálek, J; Janouškovec, J; Lai, DH; Jirků, M; Hajdušková, E; Tomčala, A; Otto, TD; Keeling, PJ; Pain, A; Oborník, M; Lukeš, J
Four respiratory complexes and ATP-synthase represent central functional units in mitochondria. In some mitochondria and derived anaerobic organelles, a few or all of these respiratory complexes have been lost during evolution. We show that the respiratory chain of Chromera velia, a phototrophic relative of parasitic apicomplexans, lacks complexes I and III, making it a uniquely reduced aerobic mitochondrion. In Chromera, putative lactate:cytochrome c oxidoreductases are predicted to transfer electrons from lactate to cytochrome c, rendering complex III unnecessary. The mitochondrial genome of Chromera has the smallest known protein-coding capacity of all mitochondria, encoding just cox1 and cox3 on heterogeneous linear...

14. Evolution of red algal plastid genomes: ancient architectures, introns, horizontal gene transfer, and taxonomic utility of plastid markers. - Janouškovec, J; Liu, SL; Martone, PT; Carré, W; Leblanc, C; Collén, J; Keeling, PJ
Red algae have the most gene-rich plastid genomes known, but despite their evolutionary importance these genomes remain poorly sampled. Here we characterize three complete and one partial plastid genome from a diverse range of florideophytes. By unifying annotations across all available red algal plastid genomes we show they all share a highly compact and slowly-evolving architecture and uniquely rich gene complements. Both chromosome structure and gene content have changed very little during red algal diversification, and suggest that plastid-to nucleus gene transfers have been rare. Despite their ancient character, however, the red algal plastids also contain several unprecedented features, including...

15. A photosynthetic alveolate closely related to apicomplexan parasites. - Moore, RB; Oborník, M; Janouskovec, J; Chrudimský, T; Vancová, M; Green, DH; Wright, SW; Davies, NW; Bolch, CJ; Heimann, K; Slapeta, J; Hoegh-Guldberg, O; Logsdon, JM; Carter, DA
Many parasitic Apicomplexa, such as Plasmodium falciparum, contain an unpigmented chloroplast remnant termed the apicoplast, which is a target for malaria treatment. However, no close relative of apicomplexans with a functional photosynthetic plastid has yet been described. Here we describe a newly cultured organism that has ultrastructural features typical for alveolates, is phylogenetically related to apicomplexans, and contains a photosynthetic plastid. The plastid is surrounded by four membranes, is pigmented by chlorophyll a, and uses the codon UGA to encode tryptophan in the psbA gene. This genetic feature has been found only in coccidian apicoplasts and various mitochondria. The UGA-Trp...

16. A common red algal origin of the apicomplexan, dinoflagellate, and heterokont plastids. - Janouskovec, J; Horák, A; Oborník, M; Lukes, J; Keeling, PJ
The discovery of a nonphotosynthetic plastid in malaria and other apicomplexan parasites has sparked a contentious debate about its evolutionary origin. Molecular data have led to conflicting conclusions supporting either its green algal origin or red algal origin, perhaps in common with the plastid of related dinoflagellates. This distinction is critical to our understanding of apicomplexan evolution and the evolutionary history of endosymbiosis and photosynthesis; however, the two plastids are nearly impossible to compare due to their nonoverlapping information content. Here we describe the complete plastid genome sequences and plastid-associated data from two independent photosynthetic lineages represented by Chromera velia...

17. Ancestry variation and footprints of natural selection along the genome in Latin American populations. - Deng, L; Ruiz-Linares, A; Xu, S; Wang, S
Latin American populations stem from the admixture of Europeans, Africans and Native Americans, which started over 400 years ago and had lasted for several centuries. Extreme deviation over the genome-wide average in ancestry estimations at certain genomic locations could reflect recent natural selection. We evaluated the distribution of ancestry estimations using 678 genome-wide microsatellite markers in 249 individuals from 13 admixed populations across Latin America. We found significant deviations in ancestry estimations including three locations with more than 3.5 times standard deviations from the genome-wide average: an excess of European ancestry at 1p36 and 14q32, and an excess of African...

18. Hereditary diffuse gastric cancer: updated consensus guidelines for clinical management and directions for future research. - Fitzgerald, RC; Hardwick, R; Huntsman, D; Carneiro, F; Guilford, P; Blair, V; Chung, DC; Norton, J; Ragunath, K; Van Krieken, JH; Dwerryhouse, S; Caldas, C; International Gastric Cancer Linkage Consortium,
25-30% of families fulfilling the criteria for hereditary diffuse gastric cancer have germline mutations of the CDH1 (E-cadherin) gene. In light of new data and advancement of technologies, a multidisciplinary workshop was convened to discuss genetic testing, surgery, endoscopy and pathology reporting. The updated recommendations include broadening of CDH1 testing criteria such that: histological confirmation of diffuse gastric criteria is only required for one family member; inclusion of individuals with diffuse gastric cancer before the age of 40 years without a family history; and inclusion of individuals and families with diagnoses of both diffuse gastric cancer (including one before the...

19. Nomenclature of genetic movement disorders: Recommendations of the international Parkinson and movement disorder society task force. - Marras, C; Lang, A; van de Warrenburg, BP; Sue, CM; Tabrizi, SJ; Bertram, L; Mercimek-Mahmutoglu, S; Ebrahimi-Fakhari, D; Warner, TT; Durr, A; Assmann, B; Lohmann, K; Kostic, V; Klein, C
The system of assigning locus symbols to specify chromosomal regions that are associated with a familial disorder has a number of problems when used as a reference list of genetically determined disorders,including (I) erroneously assigned loci, (II) duplicated loci, (III) missing symbols or loci, (IV) unconfirmed loci and genes, (V) a combination of causative genes and risk factor genes in the same list, and (VI) discordance between phenotype and list assignment. In this article, we report on the recommendations of the International Parkinson and Movement Disorder Society Task Force for Nomenclature of Genetic Movement Disorders and present a system for...

20. AKT1 genotype moderates the acute psychotomimetic effects of naturalistically smoked cannabis in young cannabis smokers. - Morgan, CJ; Freeman, TP; Powell, J; Curran, HV
Smoking cannabis daily doubles an individual's risk of developing a psychotic disorder, yet indicators of specific vulnerability have proved largely elusive. Genetic variation is one potential risk modifier. Single-nucleotide polymorphisms in the AKT1 and catechol-O-methyltransferase (COMT) genes have been implicated in the interaction between cannabis, psychosis and cognition, but no studies have examined their impact on an individual's acute response to smoked cannabis. A total 442 healthy young cannabis users were tested while intoxicated with their own cannabis-which was analysed for delta-9-tetrahydrocannbinol (THC) and cannabidiol content-and also ±7 days apart when drug-free. Psychotomimetic symptoms and working memory were assessed on...

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