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1.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 696-702, mar.-abr. 2019. tab, graf
Artigo em Português | LILACS (Américas), VETINDEX | ID: biblio-1011270

RESUMO

O objetivo do presente trabalho foi avaliar a variabilidade genética de larvas e alevinos de piracanjuba em programa de repovoamento. Foram coletadas 180 larvas de piracanjuba de três dias e 90 alevinos de três meses de idade. Foram avaliados cinco loci microssatélites, os quais produziram 19 alelos. Não houve presença de alelos raros nem perdas de alelos ao longo do período. A heterozigosidade observada foi superior nas larvas em relação aos alevinos. Houve desvio no equilíbrio de Hardy-Weinberg na maioria dos loci em ambos os grupos. O coeficiente de endogamia foi positivo em ambos os grupos, sendo a média dos alevinos superior em relação às larvas. O excesso de heterozigotos foi significativo no modelo Stepwise Mutation Model para os alevinos, indicando a possibilidade de efeito gargalo recente. Conclui-se que, apesar da adequada variabilidade genética encontrada, os valores do coeficiente de endogamia e a possibilidade de efeito gargalo nos alevinos atentam para a necessidade de constante monitoramento genético desses estoques antes da liberação no ambiente.(AU)


The objective of this study was to evaluate the genetic variability of Piracanjuba larvae and fingerlings in restocking program. A total of 180 three-day Piracanjuba larvae and 90 three-month-old fish were sampled. Five microsatellite loci were evaluated, which produced 19 alleles. There were no rare alleles or loss of alleles over the period. The observed heterozygosity was higher in larvae compared to fingerlings. There was a deviation in Hardy-Weinberg equilibrium in most loci in both groups. The inbreeding coefficient was positive in both groups, with the average of the fingerlings superior to the larvae. The excess heterozygotes were significant in the Stepwise Mutation Model for the fingerlings, indicating the possibility of a recent bottleneck effect. Despite the adequate genetic variability found, the values of the inbreeding coefficient and the possibility of bottleneck effect in the fingerlings show the need for constant genetic monitoring of these stocks prior to release into the environment.(AU)


Assuntos
Animais , Peixes , Variação Biológica da População , Endogamia
2.
Mycobiology ; : 200-206, 2019.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wprim-760539

RESUMO

Allelic differences in A and B mating-type loci are a prerequisite for the progression of mating in the genus Pleurotus eryngii; thus, the crossing is hampered by this biological barrier in inbreeding. Molecular markers linked to mating types of P. eryngii KNR2312 were investigated with randomly amplified polymorphic DNA to enhance crossing efficiency. An A4-linked sequence was identified and used to find the adjacent genomic region with the entire motif of the A locus from a contig sequenced by PacBio. The sequence-characterized amplified region marker 7-2299 distinguished A4 mating-type monokaryons from KNR2312 and other strains. A BLAST search of flanked sequences revealed that the A4 locus had a general feature consisting of the putative HD1 and HD2 genes. Both putative HD transcription factors contain a homeodomain sequence and a nuclear localization sequence; however, valid dimerization motifs were found only in the HD1 protein. The ACAAT motif, which was reported to have relevance to sex determination, was found in the intergenic region. The SCAR marker could be applicable in the classification of mating types in the P. eryngii breeding program, and the A4 locus could be the basis for a multi-allele detection marker.


Assuntos
Cruzamento , Cicatriz , Classificação , Dimerização , DNA , DNA Intergênico , Endogamia , Pleurotus , Fatores de Transcrição
4.
Electron. j. biotechnol ; 19(6): 9-11, Nov. 2016. ilus
Artigo em Inglês | LILACS (Américas) | ID: biblio-1039747

RESUMO

Background: Marker-assisted introgression currently represents the most widely spread application of DNA markers as an aid to selection in plant breeding. New barley germplasm should be supplemented by genes that facilitate growth and development under stressful conditions. The homology search against known genes is a fundamental approach to identify genes among the generated sequences. This procedure can be utilized for SNP search in genes of predicted function of interest and associated gene ontology (GO). Results: Backcross breeding enhanced by marker selection may become a powerful method to transfer one or a few genes controlling a specific trait. In the study, the integrated approach of combining phenotypic selection with marker assisted backcross breeding for introgression of LTP2 gene, in the background of semi-dwarf spring barley cultivar, was employed. This study discusses the efficiency of molecular marker application in backcrossing targeted on the selected gene. Conclusions: BC6 lines developed in this study can serve as a unique and adequate plant material to dissect the role of LTP2 gene. Due to its role in lipid transfer, the LTP2 may be crucial in lipidome modification in response to abiotic stress.


Assuntos
Seleção Genética , Hordeum/genética , Cruzamentos Genéticos , Melhoramento Vegetal/métodos , Marcadores Genéticos , Polimorfismo de Nucleotídeo Único , Endogamia
5.
Rev. bras. estud. popul ; 32(1): 121-137, Jan-Apr/2015. tab, graf
Artigo em Português | LILACS (Américas) | ID: lil-754015

RESUMO

Esse artigo tem por objetivo analisar os padrões de seletividade marital entre os casais heterossexuais e os casais homossexuais no Brasil, investigando os níveis de escolaridade, cor/raça e grupo etário. Inicialmente foi feita uma análise descritiva dos dados com o intuito de caracterizar a população estudada e os diferenciais entre os tipos de casais. Além disso, esse artigo utiliza tabelas de contingência e modelos log-lineares para compreender as formas de associações entre os casais e quais variáveis influenciam a seletividade dos parceiros. Os resultados mostram que cor/raça e escolaridade têm maior influência na seletividade dos casais heterossexuais, enquanto cor/raça e grupo etário são mais relevantes para os casais homossexuais em relação aos seus padrões de seletividade. Portanto, é possível identificar a existência de diferenças entre as características de seletividade entre esses casais e seus padrões, o que abre margem para estudos posteriores que possam aprofundar a compreensão das distinções entre esses padrões, no sentido de encontrar formas de tentar explicá-las e suas possíveis consequências no Brasil.


El objetivo de este artículo es analizar los patrones de selectividad marital entre las parejas heterosexuales y homosexuales en Brasil, investigando para ello los niveles de escolaridad, color/raza y grupo etario. Inicialmente se realizó un análisis descriptivo de los datos con el fin de caracterizar a la población estudiada y los diferenciales entre los tipos de parejas. Además, el estudio utiliza tablas de contingencia y modelos log-lineares para entender las formas de asociación entre las parejas y las variables que influyen en la selectividad de sus miembros. En relación con los patrones de selectividad, los resultados muestran que el color/raza y la escolaridad tienen mayor influencia en las parejas heterosexuales, mientras que el color/raza y el grupo etario al que se pertenece son más relevantes para las parejas homosexuales. Por lo tanto, se pueden identificar diferencias entre las características de la selectividad de estas parejas y sus patrones, lo que abre un espacio para estudios posteriores que puedan profundizar la comprensión de las diferencias entre estos patrones, con el fin de intentar explicar estas distinciones y sus posibles consecuencias en el país.


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Censos , Comportamento de Escolha , Características da Família , Heterossexualidade , Homossexualidade , Parceiros Sexuais/psicologia , Fatores Etários , Brasil , Escolaridade , Endogamia/estatística & dados numéricos , Modelos Lineares , Fatores Socioeconômicos
6.
Rev. biol. trop ; 61(2): 577-582, Jun. 2013. tab
Artigo em Inglês | LILACS (Américas) | ID: lil-675453

RESUMO

The umbu tree (Spondias tuberosa) is one of the most important endemic species to the Brazilian tropical semiarid region. The umbu tree has edible fruits with a peculiar flavor that are consumed in natura or in a semi-industrialized form, such as jams, candies and juices. The majority of endemic species to Brazilian semiarid region have not been studied or sampled to form germ- plasm collections, which increases the risk of losing genetic variability of the adapted species to xerophytic conditions. The aim of this study was to estimate outcrossing rates in S. tuberosa using a multilocus mixed model in order to guide genetic resources and breeding programs of this species. DNA samples were extracted from 92 progenies of umbu trees, which were distributed among 12 families. These trees were planted by seed in 1991 in Petrolina, PE, Brazil. The experimental design was a randomized block, with a total of 42 progenies sampled in three regions. The experimental units were composed by five plants and five replications. The out- crossing rate was estimated by the multilocus model, which is available in the MLTR software, and was based on 17 polymorphic AFLP bands obtained from AAA_CTG and AAA_CTC primer combinations. The observed heterozygotes ranged from 0.147 to 0.499, with a maximum frequency estimated for the AAA_CTC_10 ampli- con. The multilocus outcrossing estimation ( ) was 0.804±0.072, while the single-locus ( ) was 0.841±0.079, which suggests that S. tuberosa is predominantly an outcrossing species. The difference between and was -0.037±0.029, which indicates that biparental inbreeding was nearly absent. The mean inbreeding coefficient or fixation index ( ) among maternal plants was - 0.103±0.045, and the expected was 0.108, which indicates that there was no excess of heterozygotes in the maternal population. The outcrossing estimates obtained in the present study indicate that S. tuberosa is an open-pollinated species. Biometrical models applied to this species should therefore take into account the deviation from random outcrossing to estimate genetic parameters and the constitution of broad germplasm samples to preserve the genetic variability of the species. Outcrossing rates based on AFLP and the mixed-mating model should be applied to other studies of plant species in the Brazilian semiarid region.


El árbol de umbu (Spondias tuberosa) es una de las especies endémicas más importantes de la región semiárida del Brazil. El mismo tiene frutos comestibles con sabor distinto y puede ser consumido fresco o semiindustrializado, como mermeladas y zumos. La mayoría de las especies endémicas de la región semiárida del Brazil no fueron estudiadas o muestreadas para formar colecciones de germoplasma, aumentando el riesgo de pérdida de la variabilidad genética. El objetivo de este trabajo fue estimar las tasas de polinización cruzada en S. tuberosa basada en el modelo multi-locus mixto, con el fin de orientar los recursos genéticos y los programas de mejoramiento de esta especie. Muestras de ADN fueron extraídas de 92 progenies de árboles umbuzeiro, distribuidos en 12 familias, que se establecieron en Petrolina, PE, Brazil, 09º09’ S - 40º22’ W. El diseño experimental fue de bloques al azar con un total de 42 progenies muestreadas en tres regiones. La tasa de fecundación cruzada fue estimada por el modelo multi-locus disponible en el software MLTR, basado en 17 bandas de AFLP polimórficas obtenidas a partir de las combinaciones de cebadores AAA_CTG y AAA_CTC. Los heterocigotos observados oscilaron entre 0.147 y 0.499 con la frecuencia máxima estimada para AAA_CTC 10 amplicón. El valor estimado de cruzamiento multi-locus ( ) fue 0.804±0.072, mientras que el locus de uno-locus ( ) fue 0.841±0.079, lo que sugiere que S. tuberosa es predominantemente una especie de polinización cruzada. La diferencia entre el y fue de -0.037± 0,029, lo que indica que la endogamia bi-parental fue casi inexistente. La media del coeficiente de fijación ( ) entre las plantas maternas fue - 0.103±0.045, mientras que la esperada fue 0.108, lo que indica que no hubo un exceso de heterocigotos en la población materna. Las estimaciones obtenidas en este trabajo indican que S. tuberosa es una especie de polinización cruzada. Los modelos biométricos aplicados a esta especie deben tener en cuenta la desviación del cruce aleatorio para estimar los parámetros genéticos y la formación de grandes muestras para preservar la variabilidad genética de esta especie. La tasa de fecundación cruzada basada en AFLP y el apareamiento mezclado debe ser aplicado a otros estudios de especies de plantas de la región semiárida del Brazil.


Assuntos
Anacardiaceae/fisiologia , Cruzamentos Genéticos , Endogamia , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Anacardiaceae/classificação , Anacardiaceae/genética , Brasil
7.
Arq. bras. med. vet. zootec ; 64(6): 1656-1664, Dec. 2012. ilus, tab
Artigo em Português | LILACS (Américas) | ID: lil-660237

RESUMO

Foram utilizados dados de pedigree de 2.558 bovinos da raça Gir Mocha nascidos no período de 1954 a 2005. As análises foram realizadas utilizando-se o programa Endog. Do total de animais estudados, 61,9%; 10,6% e 0,1% possuíam pedigree na primeira, segunda e terceira gerações, respectivamente.O número efetivo de rebanhos que forneceram machos reprodutores foi de 10,25 para pais e 3,87 para avôs, confirmando a baixa integralidade do pedigree. O número de animais fundadores foi de 975,5, e o número efetivo de fundadores de 141,34. O número de ancestrais na população referência foi de 924 animas, dos quais apenas 39 explicaram 50% da variabilidade genética da população.O coeficiente médio de relação foi estimado em 0,75%, sendo o maior coeficiente individual de 25%. O coeficiente de endogamia foi igual a zero de 1954 a 1984. Vale salientar que, neste período, estão incluídos os animais sem ascendência conhecida. A endogamia e o coeficiente médio de relação da população foram baixos, contudo podem estar subestimados em razão da pequena integralidade do pedigree.


In this study we used data from the 2558 pedigree cattle polled Gir born from 1954 to 2005. Analyses were performed using the Endog program. Of all animals studied, 61.86%, 10.56% and 0.10% had a pedigree in the first, second and third generation, respectively. The effective number of herds that provide breeding males was 10.25 for parents and 3.87 for grandparents, corroborating the low completeness of the pedigree. The number of founder animals was 975.5 and the effective number of founders were 141.34. The number of ancestors in the reference population was 924 animals from which only 39 accounted for 50% of the genetic variability of the population. The average relationship coefficient was estimated at 0.75%, the largest individual coefficient was 25%. The inbreeding coefficient was zero from 1954 to 1894. It is noteworthy that during this period included the population was low, but may be underestimated because of the small pedigree integrity.


Assuntos
Animais , Bovinos , Endogamia , Linhagem , Mapeamento Físico do Cromossomo/veterinária
8.
Rev. biol. trop ; 60(1): 425-436, Mar. 2012. graf, tab
Artigo em Espanhol | LILACS (Américas) | ID: lil-657790

RESUMO

Genetic variability in captive populations of Crocodylus moreletii (Crocodylia: Crocodylidae) using microsatellites markers. Crocodylus moreletii, an extinction threatened species, represents an emblem for tropical ecosystems in Mexico. Surprisingly, there is a lack of information about their genetic constitution, which should be evaluated for a proper management ex situ and for making decisions on the release of crocodiles into natural habitats. The aim of this study was to characterize and compare the genetic variability of four populations of C. moreletii (two wild versus two born ex situ). Through PCR were amplified seven microsatellite polymorphic loci, however a heterozygote deficit, diminished by the presence of null alleles, was found in the populations (average H O=0.02). The AMOVA indicated that the highest proportion of genetic variability is within populations, and a limited genetic differentiation among populations (average F ST=0.03), probably due to high inbreeding index (average F IS=0.97). When comparing the genetic variability between and within other crocodilian species, we found that in C. moreletii is well below those reported. We concluded that the limited genetic variability in ex situ born populations is probably due to a founder effect derived from the social structure of their progenitors, and by the bottleneck effect, inferred by the limited effective population size, that historically characterizes their natural distribution in wild populations.


Crocodylus moreletii representa un emblema para los ecosistemas tropicales de México pero actualmente está amenazada por extinción. Sorprendentemente, hay una falta de información de su constitución genética, que debe ser evaluada para un manejo apropiado ex situ y para toma de decisiones en la liberación de cocodrilos a su hábitat natural. El objetivo del estudio fue caracterizar y comparar la variabilidad genética de cuatro grupos poblacionales de C. moreletii (dos silvestres y dos nacidas ex situ). Mediante PCR se amplificaron siete loci de microsatélites polimórficos, sin embargo se encontró déficit de heterocigotos en las poblaciones (promedio H O=0.02) mermado por la presencia de alelos nulos. El AMOVA indicó que la mayor proporción de variabilidad genética se encuentra dentro de las poblaciones y una limitada diferenciación genética entre poblaciones (promedio F ST =0.03), probablemente debida al alto índice de endogamia (promedio F IS=0.97). Al comparar la variabilidad genética inter e intra especies de cocodrilianos, encontramos que en C. moreletii está muy por debajo de los reportados. Se concluye que la limitada variabilidad genética de las poblaciones nacidas ex situ probablemente se debe al efecto fundador derivado de la estructura social de sus progenitores, y de las poblaciones silvestres, por el efecto cuello de botella, inferido por el limitado tamaño efectivo de población que presentó históricamente en su distribución natural.


Assuntos
Animais , Feminino , Masculino , Jacarés e Crocodilos/genética , Genética Populacional , Variação Genética/genética , Repetições de Microssatélites/genética , Alelos , Jacarés e Crocodilos/classificação , Frequência do Gene , Endogamia , México , Reação em Cadeia da Polimerase
9.
Indian J Hum Genet ; 2012 Jan; 18(1): 3-8
Artigo em Inglês | IMSEAR (Sudeste Asiático), GHL | ID: sea-139435

RESUMO

This paper is a brief account of the scientific work of J.B.S. Haldane (1892–1964), with special reference to early research in Human Genetics. Brief descriptions of Haldane's background, his important contributions to the foundations of human genetics, his move to India from Great Britain and the research carried out in Human Genetics in India under his direction are outlined. Population genetic research on Y-linkage in man, inbreeding, color blindness and other aspects are described.


Assuntos
Defeitos da Visão Cromática/genética , Genética/história , Genética Humana/história , História do Século XX , Humanos , Endogamia/genética , Índia , Mutismo/genética
10.
JPPS-Journal of Pakistan Psychiatric Society. 2012; 9 (1): 37-43
em Inglês | IMEMR (Mediterrâneo Oriental) | ID: emr-132520

RESUMO

To describe the relationships between depression and gender, socio-economic status, education, urban or rural living and coefficient of inbreeding in a well defined relatively homogeneous population. Descriptive study. King Edward Medical College, Lahore from January 1999 to January 2002. Subjects were interviewed and diagnosed by a trained psychiatrist and information was collected on various variables. Inbreeding coefficients were calculated from genealogical data. Of 211 persons interviewed, 182 had a lifetime diagnosis of recurrent major depression and 26 had no psychiatric diagnosis. Multiple regression analysis revealed greater severity and earlier age at onset in women than men but no significant correlation of severity or age at onset with socioeconomic status, urban versus rural living or coefficient of inbreeding. This appears to be a genetically homogenous sub-type of depression and further genetic studies may reveal underlying genetic risk factors


Assuntos
Humanos , Masculino , Feminino , Transtorno Depressivo , Depressão , População Rural , Saúde da População Rural , Endogamia , Consanguinidade , Família
11.
Genet. mol. biol ; 34(3): 443-450, 2011. graf, tab
Artigo em Inglês | LILACS (Américas) | ID: lil-595997

RESUMO

Milk yield records (305d, 2X, actual milk yield) of 123,639 registered first lactation Holstein cows were used to compare linear regression (y = β0 + β1X + e) ,quadratic regression, (y = β0 + β1X + β2X2 + e) cubic regression (y = β0 + β1X + β2X2 + β3X3 + e) and fixed factor models, with cubic-spline interpolation models, for estimating the effects of inbreeding on milk yield. Ten animal models, all with herd-year-season of calving as fixed effect, were compared using the Akaike corrected-Information Criterion (AICc). The cubic-spline interpolation model with seven knots had the lowest AICc, whereas for all those labeled as "traditional", AICc was higher than the best model. Results from fitting inbreeding using a cubic-spline with seven knots were compared to results from fitting inbreeding as a linear covariate or as a fixed factor with seven levels. Estimates of inbreeding effects were not significantly different between the cubic-spline model and the fixed factor model, but were significantly different from the linear regression model. Milk yield decreased significantly at inbreeding levels greater than 9 percent. Variance component estimates were similar for the three models. Ranking of the top 100 sires with daughter records remained unaffected by the model used.


Assuntos
Animais , Bovinos/genética , Indústria de Laticínios , Lactação , Produção de Alimentos , Endogamia
12.
Electron. j. biotechnol ; 13(6): 9-10, Nov. 2010. ilus, tab
Artigo em Inglês | LILACS (Américas) | ID: lil-591913

RESUMO

Molecular markers may accelerate selection through the identification of plants with higher proportion of recurrent parent genome, as well as identifying those plants bearing target alleles like quantitative traits loci (QTLs) for white mold resistance. The objectives of this work were: 1) to employ microsatellite markers (SSR) in order to accelerate the recovery of recurrent parent genome 2) to validate sequence characterized amplified region (SCAR) Phs associated with a QTL that confers resistance to white mold, as previously identified in bean populations. Lines G122 and M20 were crossed, which generated 267 F1 plants from backcross (BC) BC1 and 113 plants from backcross BC2.SSR polymorphic markers were adopted. The relationship between BC plants and the recurrent parent was estimated based on the recurrent genome proportion (PR) in each BC plant, and the Sorensen-Dice genetic similarity (sg ir). To determine how much the phenotypic variation is explained by SCAR Phs, 56 F1:2BC1 progenies were evaluated on the field following a random block design with two replications through the straw test method. SSR markers are efficient in identifying individuals with a greater proportion of the recurrent genome. SCAR Phs was not efficient for the indirect selection of common beans for white mold resistance.


Assuntos
Fungos , Fabaceae/genética , Fabaceae/imunologia , Ascomicetos , Cruzamentos Genéticos , Doenças das Plantas/imunologia , Endogamia , Repetições de Microssatélites , Biomarcadores , Phaseolus/genética , Phaseolus/imunologia , Seleção Genética
13.
Arq. bras. med. vet. zootec ; 62(3): 738-741, June 2010. tab
Artigo em Português | LILACS (Américas) | ID: lil-554946

RESUMO

Estudou-se o efeito da endogamia sobre as características sobrevivência (intervalos de 0-30; 30-60; 60-90 e 90-120 dias) e longevidade do escargot da espécie Helix aspersa em três gerações consecutivas de acasalamentos entre irmãos perfeitos. Os animais foram criados em laboratório com temperatura entre 20 e 25ºC e umidade relativa entre 70 a 90 por cento. O menor percentual de sobrevivência ocorreu no primeiro intervalo, mas, com o aumento da endogamia, observou-se diminuição na sobrevivência nos quatro intervalos testados. A longevidade média foi de 314 e 306 dias para as gerações um e três, respectivamente, não tendo sido observados animais em hibernação. O estudo de simulação para o caráter sobrevivência, em função do coeficiente de endogamia, indicou que se deve iniciar uma criação com, pelo menos, 100 reprodutores não aparentados.


The effect of inbreeding on longevity and viability (intervals of 0-30, 30-60, 60-90, and 90-120 days of birth) in three consecutive generations of full sibs of escargot Helix aspersa raised under laboratory conditions (20-25ºC temperature; 70-90 percent relative humidity) was studied. Inbreeding effects decreased the viability for all the studied intervals. The longevity means were 314 and 306 days, respectively to the first and third generations. Hibernating animals were not observed. Population size of at least 100 non-related mating escargots replaced after 10 generations to avoid inbreeding effect is recommended.


Assuntos
Animais , Caracois Helix , Longevidade , Taxa de Sobrevida , Endogamia
14.
Rev. biol. trop ; 57(4): 1217-1222, dic. 2009. graf, tab
Artigo em Inglês | LILACS (Américas) | ID: lil-637756

RESUMO

Habroconus semenlini is a micro-terrestrial gastropod native to South America. There are no previous studies on its biology. We studied its pattern of growth, fertility and lifespan under laboratory conditions. For this purpose, 80 snails were either grouped or kept isolated (40 animals in each condition) during their lifetime. Growth is indeterminate and the species is capable of self-fertilization with high reproductive success. Grouped snails had lower fecundity than the animals that were kept in isolation. This species has a short lifespan and only one reproductive period, which characterizes the occurrence of semelparity. Rev. Biol. Trop. 57 (4): 1217-1222. Epub 2009 December 01.


Habroconus semenlini es un gastrópodo micro-terrestre nativo de América del Sur. Actualmente se carece de estudios sobre su biología. Este estudio tuvo como objetivo verificar el patrón de crecimiento, la fecundidad y la esperanza de vida de esta especie en condiciones de laboratorio. Con este fin, 80 caracoles fueron mantenidos aislados o agrupados (40 animales en cada condición) durante su ciclo de vida. La especie tiene crecimiento indeterminado y es capaz de auto-fertilización con alto grado de éxito reproductivo. Los caracoles agrupados tuvieron menor fecundidad que los que se mantuvieron en aislamiento. Esta especie tiene una vida útil corta, y sólo un período reproductivo, lo que caracteriza la semelparidad.


Assuntos
Animais , Feminino , Masculino , Estágios do Ciclo de Vida/fisiologia , Caramujos/crescimento & desenvolvimento , Fertilidade , Endogamia , Laboratórios , Longevidade , Caramujos/fisiologia , Fatores de Tempo
15.
Arq. bras. med. vet. zootec ; 60(6): 1493-1501, dez. 2008. graf
Artigo em Português | LILACS (Américas) | ID: lil-506563

RESUMO

Foram utilizados diferentes níveis de significância genômica na seleção assistida por marcadores para estimar a endogamia média e o limite de seleção, assim como os valores fenotípicos, em características quantitativas de baixa, média e alta herdabilidade. Uma comparação entre os níveis de 1 por cento, 5 por cento, 10 por cento e 20 por cento foi realizada por meio do sistema computacional de simulação genética (GENESYS), utilizado para a simulação de três genomas (cada qual constituído de um único caráter de baixa, média ou alta herdabilidade), e das populações base e inicial. Os resultados indicaram superioridade dos níveis de significância de maior magnitude (10 por cento e 20 por cento) com relação aos valores fenotípicos, resultante de menor média endogâmica, além de menor limite de seleção ao longo das gerações sob seleção para estes níveis. Estes resultados foram observados para todas as três características, embora de forma mais expressiva para o caráter de baixa herdabilidade. Assim, apesar de os níveis de 1 por cento e 5 por cento apresentarem maior precisão na detecção de marcadores ligados a quantitative trait loci (QTL), eles conduzem a maiores médias endogâmicas e limite de seleção, propiciando ganhos fenotípicos menores.


Different levels of genomic significance were used in the selection assisted by molecular markers to estimate the medium endogamy and the selection limit, as well as the phenotypic value, for quantitative traits of low, medium, and high heritability. A comparison among the levels of genomic significance of 1 percent, 5 percent, 10 percent, and 20 percent was accomplished by a computer system of genetic simulation (GENESYS), used to simulate three genomes, each of them constituted by only one character of low, medium and high heritability, and to simulate the base and the initial populations. The results suggest superiority of higher significance levels (10 percent and 20 percent) for all phenotypic values, as a consequence of lower endogamy, and lower selection limit for low, medium, and high heritability traits, but in more expressive way for low heritability trait. Although the significant levels of 1 percent and 5 percent for molecular marker assisted selection showed a high precision in detecting markers related to a quantitative trait loci (QTLs), they lead to higher endogamy and selection limits, resulting in low phenotypic gains.


Assuntos
Marcadores Genéticos , Endogamia , Padrões de Herança , Locos de Características Quantitativas , Seleção Genética , Simulação/métodos
16.
J Environ Biol ; 2008 Jul; 29(4): 555-7
Artigo em Inglês | IMSEAR (Sudeste Asiático), GHL | ID: sea-113711

RESUMO

In the course of quantitative trait loci (QTL) analysis of the back cross (BC1) families of olive flounder (Paralichtys olivaceus), we observed significant segregation distortion at a microsatellite marker Poli9-58TUF in two crosses of informative progenies. The family 1 of the random BC1 progenies derived from a cross between a F1 male genotype (A/B) and a F1's female parent genotype (A/C) and the family 2 (A/C x A/C) displayed a strong bias in the locus from the Mendelian inheritance by the elimination of homozygous A/A genotype. The deleterious roles of the AA genotypes are suggested during the metamorphosis and it implies that the parents of these families carried a recessive gene or genes hampering development at an early stage because the offspring of the double heterozygote parents show the reduction in frequency or elimination of one homozygous class, which is an evidence for linkage between the genetic marker and gene(s) with recessive deleterious alleles. This data support a hypothesis that the region contains a recessive lethal gene or genes.


Assuntos
Alelos , Animais , Segregação de Cromossomos/genética , Cruzamentos Genéticos , Feminino , Linguado/genética , Marcadores Genéticos , Genótipo , Heterozigoto , Homozigoto , Endogamia , Ligação Genética , Masculino , Repetições de Microssatélites/genética , Locos de Características Quantitativas/genética
17.
Rev. MVZ Córdoba ; 13(1): 1138-1145, ene.-abr. 2008. tab, graf
Artigo em Espanhol | LILACS (Américas) | ID: lil-498563

RESUMO

Objetivo. Estimar los componentes de varianza genético aditivo directo y materno para peso al destete en ganado criollo Blanco Orejinegro (BON). Materiales y métodos. Se utilizaron 356 registros entre los años 1988 al 2007, del núcleo de animales BON puro de la hacienda Vegas de la Clara de la Universidad de Antioquia. El análisis fue realizado utilizando un modelo animal incluyendo los efectos fijos de sexo y época de destete, y como covariable la edad al destete y los efectos aleatorios genético directo, genético materno, ambiente permanente y residual. Resultados. El peso promedio al destete fue de 196.3 ± 31.4 kg, a una edad promedio de 271.8 ± 13.5 días. Se encontraron 21 animales endogámicos con un coeficiente de endogamia de 24.5%. La heredabilidad directa y materna fueron de 0.63 ± 0.36 y 0.22 ± 0.19 con una correlación entre el efecto directo y el materno de -0.78 ± 0.21. Conclusión. De acuerdo a los resultados, existe variabilidad genética en el núcleo BON para esta característica.


Assuntos
Animais , Lactente , Animais Domésticos , Genética , Endogamia , Animais Domésticos/crescimento & desenvolvimento , Genética/classificação , Genética/educação
18.
Iraqi Journal of Agriculture. 2008; 13 (1): 10-19
em Árabe | IMEMR (Mediterrâneo Oriental) | ID: emr-87345

RESUMO

Results showed that the Flight Ability Index [FAI] of old World Screwworm [OWS] fly chrysomya bezziana adults which emerged from irradiated pupae with 30, 45, 60 and 75 Gy of gamma ray was not affected under lab. conditions but it was effected under field condition. Result of mating competitiveness of adults emerged from irradiated pupae with 30 and 60 Gy of gamma rays and mated as follows: a- Irradiated males: unirradiated males: unirradiated females. b- Irradiated females: unirradiated females: unirradiated males. c- lrradiated females: irradiated males: unirradiated females: unirradiated males. Showed that males irradiated with 30 Gy and mated as in a: reduced and have the percentages of egg hatching and have a very good competitiveness value and this dose which caused complete sterility in C. bezziana had no effect on this parameter, moreover, 30 Gy gamma rays caused an effect to females which mated as in b: Finally the results showed that irradiated males and females with 30 Gy as in c: had a very good mating competitiveness value


Assuntos
Masculino , Feminino , Insetos , Raios gama , Endogamia , Pupa/efeitos da radiação
19.
Journal of the Egyptian Society of Parasitology. 2008; 38 (3): 1007-1024
em Inglês | IMEMR (Mediterrâneo Oriental) | ID: emr-88300

RESUMO

The mating system of B. alexandrina was studied under laboratory condition by allozyme analysis and SDS-PAGE protein analysis for parent snails and their progenies of two successive generations produced by self and cross fertilization. Allozyme analysis detected 11 genetic loci in 3 enzymes; ACP [3 loci], LDH [2 loci] and EST [6 loci]. The mean number of Allele [A], average heterozygosity over loci [H] and dendrogram from cluster analysis based on genetic distances between snail groups showed a genetic heterogeneity in parents and 1[st] generation higher than that in the 2[nd] generation. Cross-fertilization and genetic heterogeneity among snails decreased through generations. Snails practiced self-fertilization showed genetic alterations and genetic heterogeneity was either decreased or increased. SDS-PAGE profile of tissue protein revealed that the mating system in B. alexandrina showed specific bands, 204 and 214 KDa, in snails bred by self-fertilization. D value based on shared protein bands number and estimated similarity between parents and progenies showed that parents were approximately similar with self and cross progenies in 1[st] generation and only with cross progenies in 2[nd] generation as self progenies showed increase or decrease in similarity. B. alexandrina susceptibility to S. mansoni was not affected when snails were bred by cross or self fertilization


Assuntos
Caramujos , Análise Citogenética , Alelos , Eletroforese , Fertilização , Endogamia , Isoenzimas , Eletroforese em Gel de Poliacrilamida
20.
Genomics & Informatics ; : 14-17, 2008.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wprim-142409

RESUMO

GENDISCAN study (Gene Discovery for Complex traits in Asian population of Northeast area) was designed to incorporate methodologies which enhance the power to identify genetic variations underlying complex disorders. Use of population isolates as the target population is a unique feather of this study. However, population isolates may have hidden inbreeding structures which can affect the validity of the study. To understand how this issue may affect results of GENDISCAN, we estimated inbreeding coefficients in two study populations in Mongolia. We analyzed the status of Hardy-Weinberg Equilibrium (HWE), polymorphism information contents (PIC), heterozygosity, allelic diversity, and inbreeding coefficients, using 317 and 1,044 STR (short tandem repeat) markers in Orkhontuul and Dashbalbar populations. HWE assumptions were generally met in most markers (88.6% and 94.2% respectively), and single marker PIC ranged between 0.2 and 0.9. Inbreeding coefficients were estimated to be 0.0023 and 0.0021, which are small enough to assure that conventional genetic analysis would work without any specific modification. We concluded that the population isolates used in GENDISCAN study would not present significant inflation of type I errors from inbreeding effects in its gene discovery analysis.


Assuntos
Animais , Grupo com Ancestrais do Continente Asiático , Plumas , Estudos de Associação Genética , Variação Genética , Necessidades e Demandas de Serviços de Saúde , Humanos , Endogamia , Inflação , Mongólia
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