Field survey of p53-gene sequence variations in Mytilus trossulus and assessment of other potential p53-gene isoforms

加拿大政府和市政当局担心人类活动对海洋生态系统造成潜在的有害影响。例如，在低陆平原的大温哥华地区，市政废水经过处理后，在沿海的各个地方排放。为了帮助解决这些污水排放附近的生态系统健康是否有任何变化，我们正在参与一项试验，在所谓的环境影响监测（EEM）项目中，测试贻贝作为哨兵物种的使用情况。在这些程序中，除了测量诸如体型和生殖发育等基本生理参数外，还测量各种疾病的患病率和强度。例如，当地的太平洋西北海岸湾贻贝M. trossulus易患一种叫做血液瘤（HN）的类似白血病的疾病，这种疾病与人类癌症伯基茨淋巴瘤有一些相似之处。众所周知，这种疾病的爆发会消灭整个种群。因此，定期监测HN的发病率是很重要的，我们正在设计新的方法来做到这一点，同时了解这种疾病的一些机制。为了提高EEM程序在不可逆转的生态系统变化发生之前早期预测潜在有害影响的能力，我们正在专门研究基因作为HN生物标志物的使用。我们的重点是肿瘤抑制p53样基因，因为我们已经发现HN与这些基因序列变异的表达之间存在关联。因此，我们建议通过监测这些基因，我们可能能够预测贻贝种群中HN的爆发。因此，我们目前工作的目的是通过监测大温哥华地区两个海滩贻贝种群中的p53基因和HN来验证这一假设，看看基因序列和疾病之间是否存在任何共同趋势。

Canadian governments and municipalities are concerned about potentially harmful effects on the marine ecosystem caused by human activities. For example, in the lower mainland Metro Vancouver region, municipal wastewater is discharged, after treatment, at various locations along the coast. To help in addressing whether there are any changes in the health of ecosystems near to these effluent discharges, we are participating in an effort to test the use of mussels as sentinel species in so-called environmental effects monitoring (EEM) programs. In these programs, besides the basic physiological parameters such as size and reproductive development, the prevalence and intensity of various diseases are measured. For example, the local Pacific North West Coast Bay Mussel, M. trossulus, is susceptible to a leukemia-like disease called haemic neoplasia (HN), which has some similarities to a human cancer, Burkitts lymphoma. Breakouts of this disease have been known to wipe out entire populations. Therefore it is important to monitor incidences of HN regularly and we are involved in devising novel ways of doing this, while at the same time learning about some of the mechanisms of the disease. To enhance the ability of EEM programs to predict potential deleterious effects early, before irreversible ecosystem changes occur, we are specifically investigating the use of genes as biomarkers of HN. Our focus is on the tumour-suppressor p53-like genes since we have found associations between HN and expression of sequence variations of these genes. Therefore we propose that by monitoring these genes we may be able to predict HN outbreaks in mussel populations. Thus, the purpose of our current work is to test this hypothesis by monitoring p53 genes and HN in mussel populations on two beaches located in the Metro Vancouver area to see if there are any common trends between the gene sequences and the disease.