Combined Mutation And Rearrangement Screening by Quantitative PCR High-Resolution Melting: Is It Relevant for Hereditary Recurrent Fever Genes?

The recent identification of genes implicated in hereditary recurrent fevers has allowed their specific diagnosis. So far however, only punctual mutations have been identified and a significant number of patients remain with no genetic confirmation of their disease after routine molecular approaches such as sequencing. The possible involvement of sequence rearrangements in these patients has only been examined in familial Mediterranean fever and was found to be unlikely. To assess the existence of larger genetic alterations in 3 other concerned genes, MVK (Mevalonate kinase), NLRP3 (Nod like receptor family, pyrin domain containing 3) and TNFRSF1A (TNF receptor superfamily 1A), we adapted the qPCR-HRM method to study possible intragenic deletions and duplications. This single-tube approach, combining both qualitative (mutations) and quantitative (rearrangement) screening, has proven effective in Lynch syndrome diagnosis. Using this approach, we studied 113 unselected (prospective group) and 88 selected (retrospective group) patients and identified no intragenic rearrangements in the 3 genes. Only qualitative alterations were found with a sensitivity similar to that obtained using classical molecular techniques for screening punctual mutations. Our results support that deleterious copy number alterations in MVK, NLRP3 and TNFRSF1A are rare or absent from the mutational spectrum of hereditary recurrent fevers, and demonstrate that a routine combined method such as qPCR-HRM provides no further help in genetic diagnosis. However, quantitative approaches such as qPCR or SQF-PCR did prove to be quick and effective and could still be useful after non contributory punctual mutation screening in the presence of clinically evocative signs

Activation of a Dimeric Metabotropic Glutamate Receptor by Inter-Subunit Rearrangement

International audienceAlthough many G protein-coupled receptors (GPCRs) can form dimers, a possible role of this phenomenon in their activation remains elusive. A recent and exciting proposal is that a dynamic inter-subunit interplay may contribute to GPCR activation. Here we examined this possibility using a dimeric metabotropic glutamate receptor (mGluR). We first developed a system to perfectly control their subunit composition, and show that mGluR dimers do not form larger oligomers. We then examined an mGluR dimer containing one subunit in which the extracellular agonist binding domain is uncoupled from the G protein-activating transmembrane domain (TMD). Despite this uncoupling in one protomer, agonist stimulation resulted in symmetric activation of either TMD in the dimer with the same efficiency. This, plus other data, can only be explained by an inter-subunit rearrangement as the activation mechanism. Although well established for other types of receptors such as tyrosine kinase or guanylate cyclase receptors, this is the first clear demonstration that such a mechanism may also apply to GPCRs

Des Fromages Modèles Innovants pour construire la qualité d'un aliment

International audienceSYALSA : Systèmes alimentaires et santé humaineAu cœur des relations entre agriculture, alimentation et environnement, les questions de santé peuvent être un moteur pour transformer les systèmes alimentaires. L’objectif général de SYALSA est d’identifier et d’évaluer les leviers d’action susceptibles de rendre les systèmes alimentaires plus favorables à la santé humaine, à travers l’alimentation, mais aussi à travers leurs effets sur l’environnement, en prenant en compte les co-bénéfices entre santé et environnement. Le métaprogramme vise ainsi à mieux comprendre les divers facteurs et mécanismes d’interaction qui, depuis la production agricole jusqu’à la consommation alimentaire, affectent la santé humaine. Il explore les relations entre les pratiques de production et de transformation, les expositions des populations à des contaminants environnementaux, et les impacts sur la santé. Enfin, il s’attache à caractériser, évaluer et accompagner les changements manifestes ou potentiels (innovations biotechniques, politiques publiques, comportements d’acteurs) susceptibles d’améliorer les bénéfices des systèmes alimentaires sur la santé des individus et des populations. Lancé en janvier 2021, SYALSA mobilise les réflexions de la prospective scientifique interdisciplinaire « Nexus Santé

Acceptability of a sustainable technological innovation applied to traditional soft cheese: Information concerning the benefits for health and the environment can compensate for a lower hedonic appreciation

International audienceThe objective of this work was to study the reaction of consumers to a technological innovation (a radically new manufacturing process) applied to a traditional product (cheese). A traditional cheese and two cheeses resulting from a new sustainable process were evaluated by 142 consumers. These cheeses were first evaluated blind, giving rise to liking score and willingness to pay (WTP). Following a message concerning the nature of the processes used for the three cheeses, the consumers gave their WTP once again. The last two stages of the protocol consisted of successively revealing two pieces of information concerning the benefits of the new process for health and the environment and in measuring, at each of these two stages, the WTP of the consumers. Blind tasting showed that the two new cheeses were less appreciated than the traditional cheese. The information concerning the nature of the processes used did not significantly influence the WTP of the new cheeses but caused a revaluation of the traditional cheese. Information on the benefits of the new process has reduced the gap between the WTP of the three cheeses by decreasing the WTP for the traditional cheese and increasing the WTP for the new cheeses. This information made it possible to compensate for differences in liking of 1 to 2 points on a scale of 10. However, there is heterogeneity in consumer reactions. Indeed, some consumers (23%) did not appreciate the sensory properties of the new cheeses, and despite the assimilation of the information concerning the benefits of the new process, their WTP remained lower than those of traditional cheese. These results show that there is no major opposition to the application of technological innovations to traditional products such as cheese and that information concerning health and environmental benefits is positively accepted

Des Fromages Modèles Innovants pour construire la qualité d'un aliment

International audienceSYALSA : Systèmes alimentaires et santé humaineAu cœur des relations entre agriculture, alimentation et environnement, les questions de santé peuvent être un moteur pour transformer les systèmes alimentaires. L’objectif général de SYALSA est d’identifier et d’évaluer les leviers d’action susceptibles de rendre les systèmes alimentaires plus favorables à la santé humaine, à travers l’alimentation, mais aussi à travers leurs effets sur l’environnement, en prenant en compte les co-bénéfices entre santé et environnement. Le métaprogramme vise ainsi à mieux comprendre les divers facteurs et mécanismes d’interaction qui, depuis la production agricole jusqu’à la consommation alimentaire, affectent la santé humaine. Il explore les relations entre les pratiques de production et de transformation, les expositions des populations à des contaminants environnementaux, et les impacts sur la santé. Enfin, il s’attache à caractériser, évaluer et accompagner les changements manifestes ou potentiels (innovations biotechniques, politiques publiques, comportements d’acteurs) susceptibles d’améliorer les bénéfices des systèmes alimentaires sur la santé des individus et des populations. Lancé en janvier 2021, SYALSA mobilise les réflexions de la prospective scientifique interdisciplinaire « Nexus Santé

TGF beta1 polymorphisms are candidate predictors of the clinical response to rituximab in rheumatoid arthritis

International audienceObjective: To evaluate the association between several candidate single-nucleotide polymorphisms (SNPs) and responsiveness to rituximab in patients with rheumatoid arthritis (RA). Methods: Sixty-three RA patients were included. Nine genes (13 SNPs) were subsequently analyzed, including those coding for cytokines involved in synovitis (IL10, LTA, TGF beta 1, TNF-alpha, TNF receptor II) and genes associated with RA susceptibility (-C5 TRAF1, STAT4, TNFAIP3 and PTPN22). Results: Forty-four patients were defined as responders and 19 as nonresponders. TGF beta 1 Codon 10 and TGF beta 1 Codon 25 SNPs were both associated with clinical response (probability to respond to treatment with the Codon 10 C/T genotype: OR = 1.6; P = 0.002, and with the Codon 25 G/C genotype: OR = 1.6; P = 0.025). The probability to be a responder when the TGF beta Codon10 C/T and TGF beta Codon 25 G/C genotypes were co-inherited, doubled (OR = 2.6; P = 0.008). Conclusion: The TGF beta 1 SNPs are associated with a good response to rituximab therapy and as such could be useful genetic biomarkers in predicting therapy outcome. (C) 2011 Societe francaise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved

Controls used in this work.

<p>⁽¹⁾ heterozogote, ⁽²⁾ homozygote, ⁽³⁾ compound heterozygote.</p><p>*These polymorphisms were not detected by HRM.</p>†<p>Copy number variation.</p

Primers used in this study.

1<p>All primers (except HRM-qPCR MVK/9 primer) showed a PCR efficiency range between 80 and 100% (IC+/−0.2%).</p>2<p>qPCR and HRM of <i>MVK</i> exon 9 could not be performed in the same run due to low PCR efficiency. We used therefore two different primer pairs.</p>3<p>p.T348M allele specific primer.</p>4<p>Forward primers were 6FAM labeled. Nine distinct PCR sets (Multiplex A to I) were designed, each yielding a pattern of 3 to 6 peaks including the 2 control fragments (DMD and GFAP).</p