Lack of Association between Genetic Polymorphisms in Enzymes Associated with Folate Metabolism and Unexplained Reduced Sperm Counts

BACKGROUND: The metabolic pathway of folate is thought to influence DNA stability either by inducing single/double stranded breaks or by producing low levels of S-adenosyl-methionine leading to abnormal gene expression and chromosome segregation. Polymorphisms in the genes encoding enzymes in the folate metabolism pathway show distinct geographic and/or ethnic variations and in some cases have been linked to disease. Notably, the gene Methylenetetrahydrofolate reductase (MTHFR) in which the homozygous (TT) state of the polymorphism c.665C>T (p.A222V) is associated with reduced specific activity and increased thermolability of the enzyme causing mild hyperhomocysteinemia. Recently several studies have suggested that men carrying this polymorphism may be at increased risk to develop infertility. METHODOLOGY/PRINCIPAL FINDINGS: We have tested this hypothesis in a case/control study of ethnic French individuals. We examined the incidence of polymorphisms in the genes MTHFR (R68Q, A222V and E429A), Methionine synthase reductase MTRR; (I22M and S175L) and Cystathionine beta-synthase (CBS; G307S). The case population consisted of DNA samples from men with unexplained azoospermia (n = 70) or oligozoospermia (n = 182) and the control population consisted of normospermic and fertile men (n = 114). We found no evidence of an association between the incidence of any of these variants and reduced sperm counts. In addition haplotype analysis did not reveal differences between the case and control populations. CONCLUSIONS/SIGNIFICANCE: We could find no evidence for an association between reduced sperm counts and polymorphisms in enzymes involved in folate metabolism in the French population

Comparing Journalistic Role Performance Across Thematic Beats: A 37-Country Study

Studies suggest that, at the routine level, news beats function as unique “micro-cultures.” Exploring this “particularist” approach in news content, we compare how the interventionist, watchdog, loyal, service, infotainment, and civic roles materialize across 11 thematic news beats and analyze the moderating effect of platforms, ownership, and levels of political freedom on journalistic role performance in hard and soft news. Based on the second wave of the Journalistic Role Performance (JRP) project, this article reports the findings of a content analysis of 148,474 news items from 37 countries. Our results reveal the transversality of interventionism, the strong associations of some topics and roles, and the limited reach of news beat particularism in the face of moderating variables

Study on the inheritance and relationship of some morphological and fertility characters in Faba bean (Vicia faba L.)

International audienc

La stérilité mâle nucléo-cytoplasmique 447 chez la féverole (Vicia faba L.). II. - Etude du déterminisme paternel de l'instabilité phénotypique de la stérilité mâle

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Application d'une méthode immunoenzymatique à la sélection pour la stabilité de la stérilité mâle cytoplasmique chez la féverole ( Vicia faba L)

La stérilité mâle nucléocytoplasmique «447» de la féverole (Vicia faba L) manifeste de fréquentes instabilités qui s'expriment par des retours à la fertilité parmi les lignées en cours de conversion vers la stérilité. La mise en évidence de particules cytoplasmiques pseudovirales liées à la stérilité et la forte relation entre teneur en particules et degré de stabilité du maintien a permis d'envisager l'utilisation de cette teneur comme critère de sélection. Un test immunoenzymatique du type Enzyme linked immunosorbant assay (ELISA) après l'obtention d'un antisérum et d'immunoglobulines de classe G (IgG) a été développé pour mesurer la teneur en particules pseudovirales dans la plante. L'étude de cette teneur dans les divers organes de la plante, de leur répartition dans les différents niveaux foliaires, selon l'âge de la plante et selon la température, débouche sur une nouvelle méthode d'évaluation de la stérilité mâle nucléocytoplasmique «447». Cette méthode d'évaluation de la stérilité mâle est comparée à la méthode directe basée sur l'observation pollinique. La bonne héritabilité du caractère teneur en particules permet de sélectionner efficacement pour le maintien de la stérilité «447».Use of an immunoenzymatic assay in breeding for higher stability in cytoplasmic male sterile faba bean (Vicia faba L). The nucleocytoplasmic male sterility "447" of faba bean (Vicia faba L) shows frequent instabilities expressed by the occurrence of male fertile plants in backcross progenies. The discovery of cytoplasmic virus-like particles (VLPs) linked to male sterility and the observation of a strong relationship between particle contents and stability level led the breeder to utilise virus-like particle content as a selection criterion. An enzyme linked immunosorbant assay (ELISA) test has been developed through antiserum and IgG production for quantifying the VLPs. The evaluation of VLP contents in different plant organs (tables I and II), their repartition according to node level (fig 2), plant age (tables III and IV) and temperature have led to a new method for male sterility evaluation in breeding programs. The efficiency of this method appears higher when compared to the direct method of pollen observation (fig 5). The good heritability of VLP content character analyzed in figs 3 and 4 allows efficient selection for stabilizing male sterility «447»

Hybrid breeding in faba bean (Vicia faba)

INRA-Station de Zoologie-35650 Le RheuNational audienc

La stérilité mâle nucléo-cytoplasmique 447 chez la féverole (Vicia faba L.). I. - Etude du déterminisme maternel de l'instabilité phénotypique de la stérilité mâle

International audienc