The high frequency of gene methylation (with the exception of MLH1) and the high agreement between AIP and methylation of the gene promoter area for the MLH1, APC, and CDH1 genes suggest that the inactivation of tumor suppressor genes and of the genes related to the control of cellular proliferation through this mechanism is involved in gallbladder carcinogenesis.

No abstract

Alleles of vacA and cagA genes of H pylori are associated with the severity of gastric mucosal damage.

The genus Nothofagus is the main component of southern South American temperate forests. The 40 Nothofagus species, evergreen and deciduous, and some natural hybrids are spread among Central and Southern Chile, Argentina, New Zealand, Australia, New Guinea and New Caledonia. Nothofagus nervosa, Nothofagus obliqua and Nothofagus dombeyi are potentially very important timber producers due to their high wood quality and relative fast growth; however, indiscriminate logging has degraded vast areas the Chilean forest causing a serious state of deterioration of their genetic resource. The South of Chile has a large area covered by secondary forests of Nothofagus dombeyi. These forests have a high diversity of species, large amount of biomass and high silvicultural potential. This work shows a case of hybrid identification in Nothofagus subgenus in different secondary forests of Chile, using high resolution melting. Unknown samples of Nothofagus subgenus are genetically distinguishable with the ITS region of Nothofagus antarctica, Nothofagus nitida and N. obliqua species. It was not possible to distinguish between unknown samples of Andean versus coastal origin. Melting curves with ITS approach of unknown material are genetically similar, positioned between N. dombeyi and N. antarctica and distant from N. nitida. The unknown samples are genetically very close to Nothofagus dombeyi. This suggests the presence of hybrid individuality between species (N. dombeyi × N. antarctica) with the possibility of introgression towards the gene pool of N. antarctica, producing the deciduous foliage that is both present. The trnL locus has no distinction between the N. dombeyi and N. antarctica species, since a similar melting curve is present and equal Tm (80.00 °C). The trnL locus cannot be genetically distinguished from one unknown sample of Nothofagus to another, as highlighted in this study.

No abstract

Solanum fernandezianum is an endemic species in danger of extinction the Robinson Crusoe Island, Chile. The fruit was collected during March and April of 2002. The seeds were storaged for a year to 4°C. The percentage of germination in laboratory conditions was 14.3%. After 22 weeks plants initiated fl owering and fruiting. The conservation strategy considered germination of seeds, production of plants in incubation chamber, transplantation to pots and pots arranged in a greenhouse.Los recursos fi togenéticos constituyen la base biológica de la seguridad alimentaria mundial. Estos recursos, a su vez, están formados por la rica diversidad de material genético que contienen las variedades tradicionales y los cultivares modernos, así como las plantas silvestres afi nes a las cultivadas por el hombre. Además, constituyen un depósito de adaptabilidad genética que sirve de garantía ante el peligro potencial presentado por los cambios medioambientales y económicos (FAO 1996).Uno de los cultivos alimenticios mundiales más demandados es la papa (Solanum tuberosum L.), por su alto contenido de almidón, con una fuente diversa de germoplasma utilizada para su fi tomejoramiento. En este contexto se puede cruzar con la mayoría de sus parientes silvestres, incorporando resistencia a estrés (Hijmans & Spooner 2001). Entre estas papas silvestres se encuentra Solanum fernandezianum Phil., serie Etuberosum, se caracteriza morfológicamente por ser una planta herbácea rizomatosa, con tallos y hojas glabras, y fl ores de color azul violeta (Contreras & Spooner 1999). Es originaria de la Isla Robinson Crusoe en el Archipiélago de Juan Fernández, Parque Nacional y Reserva de la Biósfera de Chile, es una especie endémica con una distribución restringida sólo a esta isla en áreas semidespejadas con abundante presencia de helechos arborescentes y herbáceos, la vegetación asociada coincide con la reportada por Marticorena et al. (1998). Esta especie ha sido clasifi cada en peligro por Stuessy et al.

No abstract

Easy, economic, precise species authentication is currently necessary in many areas of research and diagnosis in molecular biology applied to conservation studies of endangered species. Here, we present a new method for the identification of three fox species of the Lycalopex genus in Chile. We developed an assay based on high‐resolution melt analysis of the mitochondrial cytochrome B gene, allowing a simple, low cost, fast, and accurate species determination. To validate the assay applicability for noninvasive samples, we collected fecal samples in the Atacama Desert, finding unexpectedly one species outside of its known distribution range. We conclude that the assay has a potential to become a valuable tool for a standardized genetic monitoring of the Lycalopex species in Chile.