Wu F Y, Tsai F J, Kuo H W, Tsai C H, Wu W Y, Wang R Y, Lai J S
Institute of Environmental Health, China Medical College, No. 91, Hsueh-Shin RD, Taichung, Taiwan.
Mutat Res. 2000 Jan 24;464(2):289-96. doi: 10.1016/s1383-5718(99)00206-5.
The frequency of sister chromatid exchanges (SCEs), high SCE frequency cells (HFCs), and genetic polymorphism of genotypes glutathione S-transferase (GST) M1 and T1 were analyzed in peripheral lymphocytes of 35 workers occupationally exposed to chromium (Cr) and 35 matched control group. Results showed that workers exposed to Cr showed 6.07 SCE/cell, as compared to 4.76 SCE/cell for the control group (p<0.01). Smokers showed a statistically significant higher frequency of SCE than non-smokers in both groups. The work duration of Cr workers was an important factor. Workers exposed for more than 5 years showed a significantly higher level of SCEs (p<0.05). Workers exposed to Cr for 5 or more years had higher HFC rates (51.4%) than those exposed for less than 5 years (22.9%), with an odds ratio of 4.5 times than those exposed for less than 5 years. In HFC analysis, Cr workers who smoked showed a higher level of HFC (60%) than the control group (5.7%) and also had a higher odds ratio (60.4) compared with the control group. Among non-smokers, the odds ratio was 9.0. Another objective of this study is to investigate the relationship between SCE and genetic polymorphisms of GST M1 and T1 in Cr workers. The results showed that the incidence of GSTM1 null genotype was 60% in the control group and 77.1% in Cr workers, and percentages of GSTT1 deletion were 42.9% and 62.9% in control and exposed individuals, respectively. There was a slightly increased frequency of SCE among Cr workers with GSTM1 null genotype as opposed to non-null genotype individuals. A similar result was seen among the control group; however, there were no statistically significant differences. In conclusion, the current study found the positive induction of SCE in workers who smoked or/and were exposed to Cr. However, different GST genotypes did not influence the level of cytogenetic damage between groups. Despite slight variation in numbers, they all appear to be not different.
分析了35名职业性接触铬（Cr）的工人及35名相匹配的对照组外周血淋巴细胞中姐妹染色单体交换（SCE）频率、高SCE频率细胞（HFC）以及谷胱甘肽S -转移酶（GST）M1和T1基因型的遗传多态性。结果显示，接触铬的工人SCE频率为6.07次/细胞，而对照组为4.76次/细胞（p<0.01）。两组中吸烟者的SCE频率在统计学上均显著高于非吸烟者。铬接触工人的工作时长是一个重要因素。接触铬超过5年的工人SCE水平显著更高（p<0.05）。接触铬5年及以上的工人HFC率（51.4%）高于接触铬不足5年的工人（22.9%），优势比是接触不足5年工人的4.5倍。在HFC分析中，吸烟的铬接触工人HFC水平（60%）高于对照组（5.7%），与对照组相比优势比也更高（60.4）。在非吸烟者中，优势比为9.0。本研究的另一个目的是调查铬接触工人中SCE与GST M1和T1基因多态性之间的关系。结果显示，对照组中GSTM1缺失基因型的发生率为60%，铬接触工人中为77.1%，对照组和接触组中GSTT1缺失的比例分别为42.9%和62.9%。与非缺失基因型个体相比，GSTM1缺失基因型的铬接触工人中SCE频率略有增加。对照组也有类似结果；然而，无统计学显著差异。总之，本研究发现吸烟或/和接触铬的工人中SCE有阳性诱导作用。然而，不同的GST基因型并未影响两组间细胞遗传学损伤水平。尽管数量上有轻微差异，但它们似乎并无不同。
