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Species that coexist nowadays will not necessarily match their distributions in the future due to different climate suitability. The aim of this study was to identify potential distribution areas where the bark beetle Dendroctonus adjunctus and six of its host tree species overlap under different climate change scenarios. Potential distribution maps were built with species presence data using the MaxLike R library. For each projection, we used WorldClim bioclimatic variables, current and future (2050, 2070) condition climate data, two greenhouse gas concentration scenarios (RCP 4.5, RCP 8.5), and three general circulation models. The results show that the projected current potential distribution area of the bark beetle extends over 216 000 [km.sup.2]. This potential distribution range spans across 28 of the 32Mexican states, eight of which have not yet reported the insect's presence. Of the 72 overlapping maps that we made, the largest covers more than 118 000 [km.sup.2] for Pinus duranguensis, while all future projections show a reduction in spatial coincidence. Given future climatic scenarios, D. adjunctus will probably reach higher altitudinal sites. The information contained in this study can be used to identify areas to prioritize monitoring, management, plant sanitation treatment, and reforestation strategies in Mexican pine forests. Key words: bark insects, RCP, MaxLike, pine forests Des especes qui coexistent aujourd'hui ne verront pas necessairement leurs distributions correspondre a l'avenir en raison de leur aptitude differente au climat. L'objectif de cette etude etait d'identifier les zones de distribution potentielles ou le scolyte Dendroctonus adjunctus et six de ses especes d'arbres hotes se chevauchent selon differents scenarios de changement climatique. Des cartes de distribution potentielle ont ete etablies a partir des donnees de presence des especes en utilisant la bibliotheque R MaxLike. Pour chaque projection, nous avons utilise les variables bioclimatiques WorldClim, les donnees climatiques des conditions actuelles et futures (2050, 2070), deux scenarios de concentration de gaz a effet de serre (RCP 4.5, RCP 8.5) et trois modeles de circulation generale. Les resultats montrent que l'aire de distribution potentielle actuelle projetee du scolyte s'etend sur 216 000 [km.sup.2]. Cette aire de distribution potentielle s'etend sur 28 des 32 Etats mexicains, dont huit n'ont pas encore signale la presence de l'insecte. Parmi les 72 cartes superposees que nous avons realisees, la plus grande couvre plus de 118 000 [km.sup.2] pour Pinus duranguensis, alors que toutes les projections futures montrent une reduction de la coincidence spatiale. Compte tenu des scenarios climatiques futurs, D. adjunctus atteindra probablement des sites plus eleves en altitude. Les informations contenues dans cette etude peuvent etre utilisees pour identifier les zones a privilegier en matiere de surveillance, de gestion, de traitement phytosanitaire et de strategies de reboisement dans les forets de pins mexicaines. [Traduit par la Redaction] Mots-cles : insectes de l'ecorce, RCP, MaxLike, forets de pins, 1. Introduction The bark beetles of Dendroctonus genus have shared habitat with Pinus through their evolutive history (Salinas-Moreno et al. 2004). Their distribution is linked to their host species (Salinas-Moreno [...]

Abstract Background Lynch syndrome (LS) is an autosomal dominant inherited cancer syndrome characterized by early onset cancers of the colorectum, endometrium and other tumours. A significant proportion of DNA variants in LS patients are unclassified. Reports on the pathogenicity of the c.1852_1853AA>GC (p.Lys618Ala) variant of the MLH1 gene are conflicting. In this study, we provide new evidence indicating that this variant has no significant implications for LS. Methods The following approach was used to assess the clinical significance of the p.Lys618Ala variant: frequency in a control population, case-control comparison, co-occurrence of the p.Lys618Ala variant with a pathogenic mutation, co-segregation with the disease and microsatellite instability in tumours from carriers of the variant. We genotyped p.Lys618Ala in 1034 individuals (373 sporadic colorectal cancer [CRC] patients, 250 index subjects from families suspected of having LS [revised Bethesda guidelines] and 411 controls). Three well-characterized LS families that fulfilled the Amsterdam II Criteria and consisted of members with the p.Lys618Ala variant were included to assess co-occurrence and co-segregation. A subset of colorectal tumour DNA samples from 17 patients carrying the p.Lys618Ala variant was screened for microsatellite instability using five mononucleotide markers. Results Twenty-seven individuals were heterozygous for the p.Lys618Ala variant; nine had sporadic CRC (2.41%), seven were suspected of having hereditary CRC (2.8%) and 11 were controls (2.68%). There were no significant associations in the case-control and case-case studies. The p.Lys618Ala variant was co-existent with pathogenic mutations in two unrelated LS families. In one family, the allele distribution of the pathogenic and unclassified variant was in trans, in the other family the pathogenic variant was detected in the MSH6 gene and only the deleterious variant co-segregated with the disease in both families. Only two positive cases of microsatellite instability (2/17, 11.8%) were detected in tumours from p.Lys618Ala carriers, indicating that this variant does not play a role in functional inactivation of MLH1 in CRC patients. Conclusions The p.Lys618Ala variant should be considered a neutral variant for LS. These findings have implications for the clinical management of CRC probands and their relatives.

Analysis of relative frequency and multiple correlations were used to determine altitude slope and exposure of places where Abies religiosa (H.B.K.) Schl. et Cham. is found in the Cofre de Perote area, state of Veracruz, México. This study includes a population structure analysis, as well as an analysis of the relationships between the common annual increment (CAI), the variables mentioned above and the coverage, the standing tree basal areas, and the stump basal areas. The results show that the fir forest is restricted to certain slope and altitude conditions. This is due primarily to the loss of forested land to agriculture. There is a 0.579 probability of finding fir trees at altitudes between 3200 and 3400 meters and on slopes of 40% to 55%. With respect to exposure, the NW side shows the greatest frequency (58%). A high correlation (r= -0.96)was found between the normal diameter (ND) and the age of the trees. Moreover, the age structure is that of a shade-tolerant species. Finally, a positive relationship was found between CAI, the stump basal area and the slope (r= 0.77, p<0.01). [ABSTRACT FROM AUTHOR]