Background: Cannabis plants and their seed have been used in many cultures as a source of medicine and feeding during history. Today, there is an increasing demand for cannabis seeds for medical use. Moreover, a seed sales market with no legal regulations has also grown. This may pose some issues if a quality control is not set in place. Identification of cannabis strains is important for quality control purposes in a nonregulated growing market and in cases of illegal traffic and medical use. Owing to the high price as a pharmacological drug, commercial products of cannabis plants and seeds for medical users are often subjected to adulterations, either when packing or distributing certified seeds in the market. Materials and Methods: Cannabis commercial seeds and cannabis seeds for medical use were analyzed with high-resolution melting (HRM) analysis using barcoding markers. Humulus lupulus L. plants from a local market were used as outgroup control. DNA barcoding uses specific regions of the genome to identify differences in the genetic sequence of conserved regions such as internal transcribed spacer (ITS) and rbc L. DNA barcoding data can be generated with real-time polymerase chain reaction combined with HRM analysis to distinguish specific conserved DNA regions of closely related species. HRM analysis is the method of choice for rapid analysis of sequence variation. Results: The melting temperature ( T _m ) of homogeneous packages was consistent with single genotypes. However, packages containing contaminating seeds showed T _m differences of 0.2°C on average. Conclusions: An effective, rapid, and low-cost method based on ITS nuclear DNA and on chloroplast rbc L regions for screening and detection of contamination in commercial cannabis seeds was developed and applied for the analysis of different samples. This approach can be used as a quality control tool for cannabis seeds or other plant material.

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.

Genomic DNA methylation, mutations and allelic deletions explain the inactivation of genes involved in cell proliferation and cell cycle control mechanisms. To analyze the methylation pattern of important genes related to different carcinogenic mechanisms in patients with breast cancer and the relationship with its biological behavior. Seventy fresh-frozen breast cancer samples were selected. The methylation specific PCR (MSP) test was used to analyze promoter methylation status for genes CDKN2A (p16), hMLH1, APC, CDH1 (Cadherin E) and FHIT. We found methylation in at least one of the genes studied in 88% of cases and in 3 or more genes in 40.5% of cases. The frequencies of promoter hypermethylation of CDKN2A, hMLH1, APC, CDH1 and FHT were 41.4%, 11.4%, 52.9%, 70% and 42.9%, respectively. We found a relationship between CDKN2A methylatlon and better survival (p=0.002). CDH1 methylation and poor histological differentiation (p=0.007), hMLH1 methylation and non-Mapuche ethnicity (p=-0.03), APC methylation and larger tumor size (p<0.05), FHIT methylatton and lack of estrogen rectptor IHC expression (p<0.05). The high frequency of promoter methylation in patients with breast cancer confirms its role in breast carcinogenesis. The finding of alterations in the methylation pattern of genes studied and its association with prognostic factors is a helpful tool in the search of new criteria for clinical and therapeutic decision making.

Morel harvesting (Morchella spp.) is relevant in Chile as a non-timber forest product, yet species-levelidentification is challenging due to the genus’ taxonomic complexity and the limited availability of local molecular studies.Here we evaluate Bar-HRM (high-resolution melting) of the ITS barcode as a rapid molecular discrimination tool, calibratedusing ITS sequencing and phylogenetic analysis. Six strains were obtained from spore prints of environmental collectionsfrom the Coastal Range (Biobío Region) and the Andean foothills (La Araucanía Region) and Aysén. ITS HRM profilesyielded four distinguishable melting patterns and were broadly consistent with three taxonomic entities recognized by ITSbasedphylogenetic placement: M. importuna, M. tridentina and M. andinensis. For M. importuna, two strains showed a ~1°C shift in melting temperature, suggesting intraspecific variation or technical effects and highlighting the need for expandedsampling to define within-species ranges. Overall, our results support Bar-HRM as a complementary rapid screening approachto discriminate previously characterized Morchella entities, with potential applications in traceability and quality control.

Throughout the world, the use of industrial polymers derived from fossil fuels is practically inevitable because they have such a wide range of applications; however, the environmental problems arising from this practice have led to a search for alternatives which will allow their use to be reduced, as well as strategies for their control by degradation using biorganic active agents. Insects have been a focus of special interest, as some species consume plastics and may serve to biodegrade them through the action of bacteria in their digestive tracts. In this context, the object of the present study was to characterise bacteria present in the intestine of wax moth larvae (Galleria mellonella). Thirty larvae were subjected to a diet based on polystyrene foam and thirty larvae in natural diet for 7 days. Gastrointestinal tracts were extracted and PCR was run. The results showed the presence of bacterial cells of Carnobacterium maltaromaticum, Brevibacterium sandarakinum, Pseudomonas psychrophila, Pseudomonas sp., Providence sp., Corynebacterium sp. However, the real action of these groups of bacteria in the effective degradation of polymers must be verified.