Fluvial Ecosystem Research, Environment Canada, 105 McGill, Montreal, QC H2Y 2E7, Canada.
Environ Sci Pollut Res Int. 2013 Feb;20(2):621-9. doi: 10.1007/s11356-012-0980-3. Epub 2012 Jun 29.
The purpose of this study was to examine the effects of pollution on DNA integrity in the feral soft-shell clam (Mya arenaria) in the Saguenay Fjord. Intertidal clams were collected downstream and upstream of the fjord at sites under anthropogenic pollution. DNA integrity was assessed by following changes in single- and double-stranded breaks, variation in DNA content and micro-nuclei (MN) incidence in hemocytes. The results revealed that clams collected at polluted sites had reduced DNA strand breaks (lower DNA repair activity), increased DNA content variation and MN frequency in hemocytes. The data revealed that DNA content variation was closely related to MN frequency and negatively with DNA strand breaks formation. Water conductivity was also related to reduced MN frequency and DNA content variation, indicating that, in addition to the effects of pollution, the gradual dilution of saltwater could compromise mussel health.
本研究旨在探讨沙格奈峡湾中野生软壳贻贝（Mya arenaria）的 DNA 完整性受污染的影响。在峡湾下游和上游的人为污染点采集潮间带贻贝。通过观察单链和双链断裂、DNA 含量变化以及血淋巴细胞中的微核（MN）发生率来评估 DNA 完整性。结果表明，在污染点采集的贻贝的 DNA 链断裂减少（DNA 修复活性降低），血淋巴细胞中的 DNA 含量变化和 MN 频率增加。数据显示，DNA 含量变化与 MN 频率密切相关，与 DNA 链断裂形成呈负相关。水导电性也与 MN 频率和 DNA 含量变化降低有关，表明除了污染的影响外，盐水逐渐稀释也会影响贻贝的健康。
