Population-level epigenetics with seafood provenance implications for the Antarctic Toothfish, Dissostichus mawsoni

This study investigates the use of DNA methylation to trace the geographical origin of Antarctic Toothfish (Dissostichus mawsoni), a species with continuous distribution around Antarctica. Traditional molecular techniques have struggled to identify location-specific genetic markers due to the population connectivity facilitated by extensive larval dispersal. However, epigenetic signals, specifically DNA methylation which can contain imprints from the local environment, offer a promising alternative as a marker for provenance. Our research identified methylation differences in toothfish harvested by fisheries in different Antarctic regions, indicating this is a promising approach to assess the origin of seafood for fishery management purposes.\nLineage: Samples originated from wild fish caught around the Antarctic continent to investigate the environmental epigenetics and adaptive potential of natural populations. High quality DNA was extracted and sequencing at AGRF, following the reduced-representation bisulfite sequencing (RRBS) approach. In the fastq files, unmethylated Cytosines have been converted to Thymines, whereas methylated CpGs remain unchanged.

本研究探讨了利用DNA甲基化（DNA methylation）追踪南极犬牙鱼（Dissostichus mawsoni）地理起源的可行性，该物种在南极洲周边呈连续分布格局。由于广泛的幼体扩散促进了种群间的连通性，传统分子技术难以鉴定出具有区域特异性的遗传标记。然而，表观遗传信号——尤其是携带有本地环境印记的DNA甲基化——为海产品产地溯源标记提供了极具潜力的替代方案。本研究在南极不同海域渔业捕捞的犬牙鱼样本中鉴定出甲基化差异，表明该方法可用于评估海产品产地来源，以服务于渔业管理工作。
样本信息：本研究样本取自南极大陆周边捕获的野生犬牙鱼，用于探究自然种群的环境表观遗传特征与适应潜力。研究采用简化代表性亚硫酸氢盐测序（reduced-representation bisulfite sequencing, RRBS）方案，在AGRF完成高质量DNA的提取与测序。在fastq格式文件中，未甲基化的胞嘧啶已被转换为胸腺嘧啶，而甲基化的CpG位点则保持不变。