Development assemblages and collective farmer-led irrigation in the Sahel: A case study from the lower Delta of the Senegal River"

In Sahelian countries, farmer-led irrigation development has contributed to the extension of irrigated areas in formerly state-led schemes, especially from the 1990s onwards. It has usually consisted of individual approaches, revealing the unequal capacities that farmers have had to develop irrigated agriculture. However, in some cases, farmers have performed collective practices geared towards achieving a more concerted and equitable management of resources. This article is centred on such collective enterprises. It is based on a case study from the delta of the Senegal River. In this region, where state agencies, donors, and investors have set the tone of irrigation development over the last decades, the concerted irrigation development led by the inhabitants of a small village (Thilène) can be considered to be a form of resistance. By drawing on the concepts of 'moral economy' and 'assemblage', and using 'comparative agriculture' methods, we situate the emergence of this collective action in order to understand who has governed it by what means or practices, and to know what have been its outcomes. We see these collective actions as an alternative irrigation development pathway to that led by the state and donors. The results highlight the contingent nature of these initiatives and the difficulties in implementing adapted policies to trigger or boost their emergence

Chapitre 5 - Sécheresse, aménagements hydrauliques et modèles de développement : delta du fleuve Sénégal

La région du delta du fleuve Sénégal (figure 5.1) connaissait déjà, avant l’épisode de sécheresse des années 1970-1980 qui a marqué l’ensemble du Sahel, de faibles totaux pluviométriques. Elle était aussi particulièrement sujette aux variations interannuelles de la pluviométrie et de la crue du fleuve, rendant l’agriculture pluviale hasardeuse (Lericollais, 1975). L’adaptation ancienne et systémique des agriculteurs et éleveurs à des..

Systèmes agraires et changement climatique au Sud

À partir de l’étude détaillée et de la comparaison d’une douzaine de situations locales contrastées en Afrique sub-saharienne et en Asie du Sud-Est, les auteurs mettent en évidence les processus et les trajectoires qui expliquent la forte exposition aux aléas des différents groupes d’agriculteurs, ainsi que leur inégale capacité d’adaptation. Ils expliquent les ressorts de cette vulnérabilité et illustrent le poids des choix passés et actuels en matière de politiques agricole, environnementale et commerciale. Enfin, ils présentent les modalités d’ajustement et les transformations passées et en cours des pratiques paysannes allant dans le sens d’une réduction de l’exposition à l’aléa, d’une atténuation de la vulnérabilité, et d’une meilleure adaptation aux changements globaux : dérèglement climatique bien sûr, mais aussi accroissement démographique, compétition accrue pour l’accès aux ressources, évolution des prix relatifs et fluctuations des marchés, dérégulation et baisse des soutiens publics, etc. Ils esquissent en conclusion les chemins possibles en matière d’adaptation et des propositions de mesures politiques pour accompagner les producteurs.Pour des raisons de différences de fabrication, les figures et photos en couleurs de la présente version sont disséminées au sein des différents chapitres, mais sont réunies à la fin du chapitre 4 de la version PDF

The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer

Abstract: Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM−/− patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors

A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

Abstract: Breast cancer (BC) risk for BRCA1 and BRCA2 mutation carriers varies by genetic and familial factors. About 50 common variants have been shown to modify BC risk for mutation carriers. All but three, were identified in general population studies. Other mutation carrier-specific susceptibility variants may exist but studies of mutation carriers have so far been underpowered. We conduct a novel case-only genome-wide association study comparing genotype frequencies between 60,212 general population BC cases and 13,007 cases with BRCA1 or BRCA2 mutations. We identify robust novel associations for 2 variants with BC for BRCA1 and 3 for BRCA2 mutation carriers, P < 10−8, at 5 loci, which are not associated with risk in the general population. They include rs60882887 at 11p11.2 where MADD, SP11 and EIF1, genes previously implicated in BC biology, are predicted as potential targets. These findings will contribute towards customising BC polygenic risk scores for BRCA1 and BRCA2 mutation carriers

Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P = 9.2 x 10(-20)), ER-negative BC (P = 1.1 x 10(-13)), BRCA1-associated BC (P = 7.7 x 10(-16)) and triple negative BC (P-diff = 2 x 10(-5)). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P = 2 x 10(-3)) and ABHD8 (PPeer reviewe

Politique hydro-agricole et résilience de l’agriculture familiale

International audienceEmblématiques des grands projets hydrauliques en Afrique de l’Ouest, les aménagements dans le Delta du fleuve Sénégal, accélérés sous l’influence de la profonde sécheresse au Sahel, ont permis de sécuriser la production en basculant d’une agriculture pluviale et de décrue à une agriculture irriguée. Ils ont en revanche conduit à un bouleversement complet des écosystèmes et de l’agriculture du Delta, dans des contextes de politiques agricoles et de modèles de développement très différents des années 1960 à aujourd’hui, qui ont continûment mis à l’épreuve la résilience de l’agriculture familiale de cette région. Demeurent aujourd’hui des insécurités dans l’accès au foncier, au capital et aux marchés pour lesquelles différentes voies d’adaptation peuvent être envisagées, qui permettent d’interroger la notion de résilience

A new hybrid record linkage process to make epidemiological databases interoperable: application to the GEMO and GENEPSO studies involving BRCA1 and BRCA2 mutation carriers

International audienceBackground: Linking independent sources of data describing the same individuals enable innovative epidemiological and health studies but require a robust record linkage approach. We describe a hybrid record linkage process to link databases from two independent ongoing French national studies, GEMO (Genetic Modifiers of BRCA1 and BRCA2), which focuses on the identification of genetic factors modifying cancer risk of BRCA1 and BRCA2 mutation carriers, and GENEPSO (prospective cohort of BRCAx mutation carriers), which focuses on environmental and lifestyle risk factors.Methods: To identify as many as possible of the individuals participating in the two studies but not registered by a shared identifier, we combined probabilistic record linkage (PRL) and supervised machine learning (ML). This approach (named "PRL + ML") combined together the candidate matches identified by both approaches. We built the ML model using the gold standard on a first version of the two databases as a training dataset. This gold standard was obtained from PRL-derived matches verified by an exhaustive manual review. Results The Random Forest (RF) algorithm showed a highest recall (0.985) among six widely used ML algorithms: RF, Bagged trees, AdaBoost, Support Vector Machine, Neural Network. Therefore, RF was selected to build the ML model since our goal was to identify the maximum number of true matches. Our combined linkage PRL + ML showed a higher recall (range 0.988-0.992) than either PRL (range 0.916-0.991) or ML (0.981) alone. It identified 1995 individuals participating in both GEMO (6375 participants) and GENEPSO (4925 participants).Conclusions: Our hybrid linkage process represents an efficient tool for linking GEMO and GENEPSO. It may be generalizable to other epidemiological studies involving other databases and registries

Classification of 101 BRCA1 and BRCA2 variants of uncertain significance by cosegregation study: A powerful approach

International audienc

Classification of 101 BRCA1 and BRCA2 variants of uncertain significance by cosegregation study: A powerful approach

International audienc