Biology, diversity and tools for diversity analysis of the onion (Allium cepa L.). A review. Description of the subject. This study explores important information on biology, genetic resources, ...taxonomy, as well as morphological, biochemical and molecular markers in order to provide a better understanding of the genetic diversity of the onion (Allium cepa L.). The study has a particular focus on the plant as grown in Africa. The onion is a monocotyledonous, allogamous, and entomophilous plant, with a one-year production cycle for bulb production, and a two-year production cycle for seeds. The onion is one of the most significant vegetables in the world because of its use as both a food and a medicine. Literature. Twenty-eight morphological markers, linked to seed, leaf, flower and bulb traits, were identified as the most discriminant phenotypical criteria. Biochemical and molecular markers were also developed to characterize genetic variations between and within onion varieties. Previous studies examining West Africa onion varieties showed that only six enzyme systems are polymorphic. However, only twenty-four isozymes have been used to compare the onion to other Allium species. This low number of polymorphic biochemical markers makes it more difficult to determine the genetic diversity of onions. On the other hand, molecular markers at DNA level, such as RAPD, RFLP, AFLP, SSR, are very useful to analyze diversity at varietal and species level, using cultivated and spontaneous forms, and to analyze the level of introgression between the onion and the other species of the genus. Conclusions. Genetic diversity analysis showed an important variability between and within Africa onion landraces. It would be useful to combine in situ and ex situ conservation, using these genetic resources to improve the production and the appropriate use of African onion cultivars.
Description du sujet. Cette étude synthétise les principaux résultats sur la biologie de l’oignon, les ressources phytogénétiques, la position taxonomique ainsi que les marqueurs morphologiques, ...biochimiques et moléculaires pour l’analyse de la diversité génétique de l’oignon, avec une attention particulière pour l’Afrique. Plante monocotylédone, allogame, entomophile, avec un cycle cultural annuel pour la production des bulbes, bisannuel pour celle des graines, l’oignon est l’un des légumes les plus importants au monde en raison de son utilisation en alimentation et en médecine. Littérature. Afin de caractériser la diversité génétique de l’oignon, 28 marqueurs morphologiques ont été définis sur base de l’observation des graines, des feuilles, des fleurs et des bulbes. Des marqueurs biochimiques et moléculaires ont aussi été développés, notamment pour analyser les variations génétiques entre et à l’intérieur des variétés. Des études entre les variétés de l’oignon d’Afrique de l’Ouest ont montré que seules six enzymes sont polymorphes. Toutefois, 24 enzymes ont été utilisées pour analyser la diversité génétique entre l’espèce Allium cepa et les autres espèces du genre Allium. Ce nombre limité de marqueurs biochimiques polymorphes rend difficile l’analyse de la diversité génétique chez l’oignon. Les marqueurs moléculaires directement issus du polymorphisme existant au niveau de l'ADN, comme RAPD, RFLP, AFLP, SSR, sont très utiles pour différencier les différentes variétés de l’oignon, pour distinguer l’espèce des autres espèces cultivées et spontanées du genre Allium et pour analyser les niveaux d’introgression entre l’oignon et d’autres espèces du genre.Conclusions. L’analyse de la diversité génétique montre une importante variabilité entre et à l’intérieur des écotypes d’oignon en Afrique. Il est donc utile de combiner des stratégies de conservation in situ et ex situ, et l’exploitation de ces ressources génétiques pour améliorer leurs productions et leurs rusticités.
Biology, diversity and tools for diversity analysis of the onion (Allium cepa L.). A reviewDescription of the subject. This study explores important information on biology, genetic resources, taxonomy, as well as morphological, biochemical and molecular markers in order to provide a better understanding of the genetic diversity of the onion (Allium cepa L.). The study has a particular focus on the plant as grown in Africa. The onion is a monocotyledonous, allogamous, and entomophilous plant, with a one-year production cycle for bulb production, and a two-year production cycle for seeds. The onion is one of the most significant vegetables in the world because of its use as both a food and a medicine. Literature. Twenty-eight morphological markers, linked to seed, leaf, flower and bulb traits, were identified as the most discriminant phenotypical criteria. Biochemical and molecular markers were also developed to characterize genetic variations between and within onion varieties. Previous studies examining West Africa onion varieties showed that only six enzyme systems are polymorphic. However, only twenty-four isozymes have been used to compare the onion to other Allium species. This low number of polymorphic biochemical markers makes it more difficult to determine the genetic diversity of onions. On the other hand, molecular markers at DNA level, such as RAPD, RFLP, AFLP, SSR, are very useful to analyze diversity at varietal and species level, using cultivated and spontaneous forms, and to analyze the level of introgression between the onion and the other species of the genus.Conclusions. Genetic diversity analysis showed an important variability between and within Africa onion landraces. It would be useful to combine in situ and ex situ conservation, using these genetic resources to improve the production and the appropriate use of African onion cultivars.
Oxidative stress and detoxification mechanisms have been commonly studied in Prostate Cancer (PCa) due to their function in the detoxification of potentially damaging reactive oxygen species (ROS) ...and carcinogens. However, findings have been either inconsistent or inconclusive. These mixed findings may, in part, relate to failure to consider interactions among oxidative stress response related genetic variants along with pro- and antioxidant factors.
We examined the effects of 33 genetic and 26 environmental oxidative stress and defense factors on PCa risk and disease aggressiveness among 2,286 men from the Cancer Genetic Markers of Susceptibility project (1,175 cases, 1,111 controls). Single and joint effects were analyzed using a comprehensive statistical approach involving logistic regression, multi-dimensionality reduction, and entropy graphs.
Inheritance of one
T or two
A alleles was linked to a 1.3- and 1.4-fold increase in risk of developing PCa, respectively (
-value = 0.006-0.013). Carriers of
and,
(
) genotypes were associated with a 1.3 to 2.2-fold increase in aggressive PCa
-value = 0.04-0.001, FDR 0.088-0.939. We observed a 23% reduction in aggressive disease linked to inheritance of one or more
A alleles (
= 0.04, FDR = 0.405). Only three
sequence variants remained significant after adjusting for multiple hypotheses testing, namely
, and
. Lastly, there were no significant gene-environment or gene-gene interactions associated with PCa outcomes.
Variations in genes involved in oxidative stress and defense pathways may modify PCa. Our findings do not firmly support the role of oxidative stress genetic variants combined with lifestyle/environmental factors as modifiers of PCa and disease progression. However, additional multi-center studies poised to pool genetic and environmental data are needed to make strong conclusions.
A pesar de todos los esfuerzos realizados por más de una década, las bases genéticas de muchas enfermedades comunes y complejas aún siguen siendo desconocidas, sin desmeritar los notables avances que ...se han logrado con los estudios de ligamiento en familias y de asociación con genes candidatos. Recientemente, el desarrollo de metodologías más robustas, como los estudios de asociación con rastreos genómicos (GWAs), ha permitido replicar asociaciones ya reportadas y a la vez descubrir nuevos genes posiblemente asociados. Los GWAs se basan en la utilización de un número considerable de marcadores genéticos tipo SNPs o STRs, los cuales son detectados con el propósito de encontrarlos asociados con la aparición y/o desarrollo de ciertas enfermedades. Teniendo en cuenta el gran impacto que actualmente tienen los GWAs como herramienta genética en la búsqueda de asociaciones, se hace una revisión teórica acerca del diseño e interpretación de los resultados de los mismos y su contribución en el asma y fenotipos relacionados.
The present paper reports the distribution of A1A2BO and Rh(D) blood groups among the Brahmins of Mussoorie, Uttaranchal. The frequency of blood group A is found to be highest. Frequency of Rh(D) ...positive is as much as 67.24%. When compared with the other studies available from Uttaranchal, present caste group - Brahmins falls in closer to the other population groups of Uttaranchal.
Differentiation of elite Indian Maize hybrids using simple sequence repeat markers Pushpavalli, S.N.C.V.L; Prasanna, B.M.(Indian Agricultural Research Institute, New Delhi(India). Division of Genetics)Sudan, C; Singh, N.N.(Indian Agricultural Research Institute, New Delhi(India). Directorate of Maize Research)
Indian journal of genetics & plant breeding,
(Nov 2001), Letnik:
61, Številka:
4
Journal Article
As an initial attempts towards molecular characterisation of maize hybrids released by public sector institutions in India, 10 popular hybrids, including six released and four promising experimental ...hybrids, were profiled using 20 polymorphic microsatellite or Simple Sequence Repeat (SSR) markers. The utility of SSRs dofferentiating the selected hybrids was demonstrated using high-resolution agarose gel electrophoresis. The polymorphic SSRs markers identified in this study could clearly distinguish single-cross hybrids developed at Ludhiana, Delhi, Almora and Hyderabad. Cluster analysis based on SSR data delineated the selected hybrids into three distinct groups. While Paras showed considerable genetic similarity with the experimental hybrids developed at Hyderabad, Vivek Hybrid-4 and Vivek Hybrid-5 (from Almora) were found to be genetically distant from other hybrids. The cluster pattern was in close agreement with the pedigree of the parental lines of the single-cross hybrids analyzed in the study.
Cette étude synthétise les principaux résultats sur la biologie de l'oignon, les ressources phytogénétiques, la position taxonomique ainsi que les marqueurs morphologiques, biochimiques et ...moléculaires pour l'analyse de la diversité génétique de l'oignon, avec une attention particulière pour l'Afrique. Plante monocotylédone, allogame, entomophile, avec une cycle cultural annuel pour la production des bulbes, bisannuel pour celles des graines, l'oignon est l'un des légumes les plus importants au monde en raison de son utilisation en alimentation et en médecine.
This study explores important information on biology, genetic resources, taxonomy, as well as morphological, biochemical and molecular markers in order to provide a better understanding of the genetic diversity of the onion (Allium cepa L.). The study has a particular focus on the plant as grown in Africa. The onion is a monocotyledonous, allogamous, and entomophilous plant, with a one-year production cycle for bulb production, and a two-year production cycle for seeds. The onion is one of the most significant vegetables in the world because of its use as both a food and a médicine.
Pistacia lentiscus var. chia is a valuable crop for its high-added-value mastic, a resin with proven pharmaceutical and cosmeceutical properties harvested from the male tree trunk. To achieve the ...maximum economic benefits from the cultivation of male mastic trees, it is important to develop early sex diagnosis molecular tools for distinguishing the sex type. Thus far, the work on sex identification has focused on Pistacia vera with promising results; however, the low transferability rates of these markers in P. lentiscus necessitates the development of species-specific sex-linked markers for P. lentiscus var. chia. To our knowledge, this is the first report regarding: (i) the development of species-specific novel transcriptome-based markers for P. lentiscus var. chia and their assessment on male, female and monoecious individuals using PCR-HRM analysis, thus, introducing a cost-effective method for sex identification with high accuracy that can be applied with minimum infrastructure, (ii) the effective sex identification in mastic tree using a combination of different sex-linked ISSR and SCAR markers with 100% accuracy, and (iii) the impact evaluation of sex type on the genetic diversity of different P. lentiscus var. chia cultivars. The results of this study are expected to provide species-specific markers for accurate sex identification that could contribute to the selection process of male mastic trees at an early stage for mass propagation systems and to facilitate future breeding efforts related to sex-linked productivity and quality of mastic resin.
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