962 resultados para Multifactorial Inheritance
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We found evidence of autosomal dominant hereditary transmission of sulcus vocalis. Four dysphonic patients from three generations of the same family were submitted to videolaryngoscopic examination (three patients) and to direct laryngoscopy ( one patient) to diagnose the hoarseness. Sulcus vocalis was diagnosed in all four patients. The finding of four affected individuals in three generations, with vertical transmission affecting man and women, is more consistent with autosomal dominant inheritance pattern; it is an etiological model that we propose for the sulcus vocalis in this pedigree.
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Silver nitrate staining of rainbow trouts (Oncorhynchus mykiss) chromosomes, for the identification of the nucleolar organizing regions (NORs), revealed that in individuals from Nucleo Experimental de Salmonicultura de Campos do Jordao (Brazil) NORs were located in the long arms of a submetacentric pair while in specimens from Mount Shasta (USA) NORs were located in the short arms of a submetacentric pair. Cytogenetic analysis of the offspring, obtained through artificial crosses including individuals from both stocks, allowed the identification of NORs in two submetacentric chromosomes, one in the short arms and the other in the long arms, confirming the effectiveness of the hybridization process. Complementary results obtained using the FISH technique with 18S and 5S rDNA probes showed that NOR-bearing chromosomes exhibited a cluster of 5S genes located in tandem with the 18S gene cluster in both stocks. The results allow us to suggest that the difference in NOR-bearing chromosomes found between the two stocks is likely to be due to a pericentric inversion involving the chromosome segment where 18S and 5S rDNA genes are located. The presence of ribosomal genes in the long arms of a submetacentric chromosome is apparently a particular characteristic of the rainbow trout stock of Campos do Jordao and might be used as a chromosome marker in studies of controlled crosses in this species.
Supernumerary chromosome inheritance in the curimbata (Prochilodus lineatus) of the Mogi-Guacu River
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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A herança da resistência ao oídio na cultivar de ervilha MK-10 e alguns aspectos histológicos da infecção foram estudados. Para o estudo da herança, as gerações F1, F2, retrocuzamentos e geração F3 de MK-10 com duas populações suscetíveis foram avaliadas. Nas avaliações histológicas observou-se a porcentagem de conídios germinados, porcentagem de conídios que formaram apressório, porcentagem de conídios que estabeleceram colônia e número de haustórios por colônia. Para comparar as razões de segregação obtidas no estudo da herança da resistência, adotou-se o teste do Qui-quadrado (X²) e para os dados das análises histológicas, utilizou-se o teste Tukey a 5% de probabilidade. Concluiu-se que a resistência de MK-10 ao oídio é devida a um par de alelos recessivos e que a resistência é expressa na fase de pré-penetração, completada por uma morte celular localizada pós-penetração, característica da presença do par de alelos recessivos er1er1.
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Milk yield, fat yield, and fat percentage during the first three lactations were studied using New York Holsteins that were milked twice daily over a 305-d, mature equivalent lactation. Those data were used to estimate variances from direct and maternal genetic effects, cytoplasmic effects, sire by herd interaction, and cow permanent environmental effects. Cytoplasmic line was traced to the last female ancestor using DHI records from 1950 through 1991. Records were 138,869 lactations of 68,063 cows calving from 1980 through 1991. Ten random samples were based on herd code. Samples averaged 4926 dams and 2026 cytoplasmic lines. Model also included herd-year-seasons as fixed effects and genetic covariance for direct-maternal effects. Mean estimates of the effects of maternal genetic variances and direct-maternal covariances, as fractions of phenotypic variances, were 0.008 and 0.007 for milk yield, 0.010 and 0.010 for fat yield, and 0.006 and 0.025 for fat percentage, respectively. Average fractions of variance from cytoplasmic line were 0.011, 0.008, and 0.009 for milk yield, fat yield, and fat percentage. Removal of maternal genetic effects and covariance for maternal direct effects from the model increased the fraction of direct genetic variance by 0.014, 0.021, and 0.046 for milk yield, fat yield, and fat percentage; little change in the fraction was due to cytoplasmic line. Exclusion of cytoplasmic effects from the model increased the ratio of additive direct genetic variance to phenotypic variance by less than 2%. Similarly, when sire by herd interaction was excluded, the ratio of direct genetic variance to phenotypic variance increased 1% or less.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Water and saline intake is controlled by several mechanisms activated during dehydration. Some mechanisms, such as the production of angiotensin II and unloading of cardiovascular receptors, activate both behaviors, while others, such as the increase in blood osmolality or sodium concentration, activate water, but inhibit saline intake. Aldosterone probably activates only saline intake. Clonidine, anα2-adrenergic agonist, inhibits water and saline intake induced by these mechanisms. One model to describe the interactions between these multiple mechanisms is a wire-block diagram, where the brain circuit that controls each intake is represented by a summing point of its respective inhibiting and activating factors. The α2-adrenoceptors constitute an inhibitory factor common to both summing points.
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Autism is a neurodevelopmental disorder characterized by impaired social interaction and communication accompanied with repetitive behavioral patterns and unusual stereotyped interests. Autism is considered a highly heterogeneous disorder with diverse putative causes and associated factors giving rise to variable ranges of symptomatology. Incidence seems to be increasing with time, while the underlying pathophysiological mechanisms remain virtually uncharacterized (or unknown). By systematic review of the literature and a systems biology approach, our aims were to examine the multifactorial nature of autism with its broad range of severity, to ascertain the predominant biological processes, cellular components, and molecular functions integral to the disorder, and finally, to elucidate the most central contributions (genetic and/or environmental) in silico. With this goal, we developed an integrative network model for gene-environment interactions (GENVI model) where calcium (Ca2+) was shown to be its most relevant node. Moreover, considering the present data from our systems biology approach together with the results from the differential gene expression analysis of cerebellar samples from autistic patients, we believe that RAC1, in particular, and the RHO family of GTPases, in general, could play a critical role in the neuropathological events associated with autism. © 2013 Springer Science+Business Media New York.
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Generation means was used to study the mode of inheritance of resistance to anthracnose stalk rot in tropical maize. Each population was comprised of six generations in two trials under a randomized block design. Inoculations were performed using a suspension of 105 conidia mL(-1) applied into the stalk. Internal lesion length was directly measured by opening the stalk thirty days after inoculation. Results indicated contrasting modes of inheritance. In one population, dominant gene effects predominated. Besides, additive x dominant and additive x additive interactions were also found. Intermediate values of heritability indicated a complex resistance inheritance probably conditioned by several genes of small effects. An additive-dominant genetic model sufficed to explain the variation in the second population, where additive gene effects predominated. Few genes of major effects control disease resistance in this cross. Heterosis widely differed between populations, which can be attributed to the genetic background of the parental resistant lines.
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The aim of this study was to evaluate factors associated with reported work-related musculoskeletal symptoms among aircraft assembly workers. Population consisted of 552 (491 men/61 women) workers who performed tasks related to the work of aircraft assembly. Participants completed a comprehensive questionnaire, including socio-demographic information, habits/lifestyles, working conditions, and work organization. Workers also answered the Nordic Musculoskeletal Questionnaire to obtain data on musculoskeletal symptoms. Multivariate logistic regression was performed to analyze factors associated with musculoskeletal reported symptoms. Results showed that body regions with the highest prevalence of reported musculoskeletal symptoms were similar when referred the past twelve months and the past seven days. Significant factors associated with musculoskeletal symptoms included variables related to conflicts at work, sleep problems, mental fatigue, and lack of time for personal care and recovery. Working time in the industry was associated only with reports for the last seven days and regular physical activity off-work seems to be a positive factor in preventing musculoskeletal symptoms for the past twelve months. The results highlight the multi-factorial nature of the problem. Actions to prevent musculoskeletal diseases at the aircraft assembly work should consider multiple interventions that would promote better recovery between work shifts.