RESUMO
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 rbcL. 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 (Tm) of homogeneous packages was consistent with single genotypes. However, packages containing contaminating seeds showed Tm differences of 0.2°C on average. Conclusions: An effective, rapid, and low-cost method based on ITS nuclear DNA and on chloroplast rbcL 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.
Assuntos
Cannabis , Código de Barras de DNA Taxonômico , Cannabis/genética , Cloroplastos/genética , Código de Barras de DNA Taxonômico/métodos , DNA Intergênico , DNA de Plantas/genética , Controle de Qualidade , Sementes/genéticaRESUMO
La metodología de investigación es una herramienta indispensable en el quehacer del clínico actual. Mucha sino toda la información pertinente en medicina crítica proviene de artículos en revistas de medicina los cuales deben ser analizados cuidadosamente en cuanto a su diseño, población en estudio, validez interna y generalización de los resultados a los pacientes que en particular atendemos día a día. En una serie de 4 artículos de revisión exploraremos los distintos aspectos de este acápite básico de muchas ciencias entre las que destaca la Epidemiología Clínica, como puente entre la mejor obtención de datos de poblaciones a nuestros contextos clínicos reales. Nuestro objetivo es dar herramientas funcionales a todos aquellos que compartimos la medicina intensiva como norte laboral y académico.
The investigation methodology is an indispensable tool in the clinical task of today. Much if not all the pertinent critical care information come from articles present in medical journals, which must be carefully analyzed, about their design, study population, internal validity and standardization of the results to the patients that we treat every day. In a series of 4 articles we will explore the different aspects of these basic paragraphs of many sciences in which the Clinical Epidemiology is very important as a bridge between the best obtaining of population results and our real clinical context. Our goal is to give functional tools to all who share the critical care as a labour and as an academic north.