The Thunnini, or tuna, comprise many species with very different commercial values. The principal raw tuna product on the market is sashimi, for which the species used is difficult to identify through conventional morphological analysis. The present study amplified the cytochrome b gene (Cytb) of 4 major tuna species used for preparing sashimi—yellowfin tuna (Thunnus albacares), southern bluefin tuna (Thunnus maccoyii), bigeye tuna (Thunnus obesus), and Atlantic bluefin tuna (Thunnus thynnus)—and 4 species commonly mislabeled as components of tuna sashimi—albacore tuna (Thunnus alalunga), skipjack tuna (Katsuwonus pelamis), striped marlin (Tetrapturus audax), and swordfish (Xiphias gladius). Polymerase chain reaction (PCR) amplicons were digested with 5 restriction enzymes—Eco147 I, Hinf I, Mbo I, Xag I, and Hind II—to obtain characteristic restriction maps of the above‐mentioned raw tuna species and the commonly mislabeled species. An identification method using PCR restriction fragment length polymorphism (PCR‐RFLP) was established and validated using 39 commercial tuna sashimi samples, which verified that this method provides results consistent with those obtained by classical sequencing. PCR‐RFLP has several advantages over classical sequencing, such as simplicity, speed and accuracy. This technique could support species identification for raw tuna and sashimi.

中文翻译：

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PCR-RFLP技术在金枪鱼生鱼片中鉴定的应用。

金枪鱼或金枪鱼包含许多具有非常不同的商业价值的物种。市场上主要的生金枪鱼产品是生鱼片，其所用物种很难通过常规形态分析来鉴定。本研究扩增了用于制备生鱼片的四种主要金枪鱼物种的细胞色素b基因（Cytb）–黄鳍金枪鱼（Thunnus albacares），南部蓝鳍金枪鱼（Thunnus maccoyii），大眼金枪鱼（Thunnus obesus）和大西洋蓝鳍金枪鱼（Thunnus thynnus））和4种通常被误标签为金枪鱼生鱼片的成分-长鳍金枪鱼（Thunnus alalunga），skip鱼（Katsuwonus pelamis）），条纹马林鱼（Tetrapturus audax）和箭鱼（Xiphias gladius）。用5种限制酶（Eco 147 I，Hinf I，Mbo I，Xag I和Hind）消化聚合酶链反应（PCR）扩增子II-获得上述生金枪鱼物种和常见标签错误物种的特征性限制图。建立了使用PCR限制性片段长度多态性（PCR-RFLP）的鉴定方法，并使用39个商业金枪鱼生鱼片样品进行了验证，这证明该方法提供的结果与经典测序获得的结果一致。与传统测序相比，PCR‐RFLP具有多个优势，例如简单，快速和准确。该技术可以为生金枪鱼和生鱼片的物种鉴定提供支持。