Escola de Ciências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
Instituto Nacional de Ciência e Tecnologia - INCT Ciências Forenses, Rio de Janeiro, Brazil.
Int J Legal Med. 2020 Sep;134(5):1603-1612. doi: 10.1007/s00414-020-02338-5. Epub 2020 Jun 25.
According to the Brazilian Federal Police (BFP), the Brazilian Cannabis sativa illicit market is mainly supplied by drugs originated from Paraguay and Northeastern Brazil (Marijuana Polygon region). These two known routes, the increasing indoor cultivations (supported by online market), and drugs from Uruguay are also in BFP's sight. Forensic tools to aid police intelligence were published in the past years. In genetics, microsatellites have gained attention due to their individualization capability. This study aims to evaluate the effectiveness and efficiency of two STR multiplex systems previously proposed in 94 Cannabis sativa samples seized in Brazil. Principal coordinate analyses (PCoA), forensic parameters, and genetic structure analysis were executed. Both panels were effective in individualizing and origin discriminating all samples, and the system proposed in 2015 demonstrated better results. For this marker set, the probability of identity for a random individual is approximately one in 65 billion; also, the PCoA shows a clear genetic distinction among samples according to its origin. Bayesian inference populational structure analysis indicated a significant genetic diversity among seizure groups, matching with its origin. Overall, the STR multiplex systems were able to achieve its purpose in individualizing and differentiating, according to geographic region, Brazilian Cannabis sp. samples.
根据巴西联邦警察局（BFP）的报告，巴西大麻的非法市场主要由源自巴拉圭和巴西东北部（大麻多边形地区）的毒品供应。这两个已知的来源，以及室内种植的增加（由在线市场支持）和来自乌拉圭的毒品，也在 BFP 的关注范围内。过去几年已经发布了用于警方情报的法医工具。在遗传学中，微卫星因其个体化能力而受到关注。本研究旨在评估过去提出的两种 STR 多重检测系统在巴西缴获的 94 份大麻样本中的有效性和效率。进行了主坐标分析（PCoA）、法医参数和遗传结构分析。这两个面板都能有效地对所有样本进行个体识别和起源区分，并且 2015 年提出的系统效果更好。对于这个标记集，随机个体的同一性概率约为六十亿分之一；此外，PCoA 根据样本的起源显示出明显的遗传差异。贝叶斯推断群体结构分析表明，扣押组之间存在显著的遗传多样性，与起源相符。总的来说，STR 多重检测系统能够根据地理区域实现对巴西大麻样本的个体识别和区分。
