锰接触工人神经行为改变与Parkin基因7号外显子多态性的关系

目的]探讨锰接触工人神经行为改变与Parkin基因7号外显子Gly284Arg多态性的相关性. 方法]选工龄在半年以上的职业性锰暴露工人200名和劳动强度相似,但工作环境不接触锰工人94名,按猛累积暴露指数将其分为高、低猛暴露组和对照组.利用沟槽稳定试验和拼板试验进行神经行为改变检测;利用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法对Parkin基因7号外显子多态性位点进行基因分型. 结果]高暴露组中,Parkin基因7号外显子CC型工人的划痕长度、拼板试验得分均低于GG型和GC型,而碰撞次数高于GG型和GC型,其差别有统计学意义(P＜0.05);低暴露组中,Parkin基因7号外显子CC型工人的划痕长度、拼板试验得分均低于GG型和GC型,其差别有统计学意义(P＜0.05),3个基因型工人碰撞次数间差别无统计学意义(P＞0.05);对照组中,Parkin基因7号外显子3个基因型划痕长度、碰撞次数、拼板试验得分之间差异无统计学意义(P＞0.05). 结论]环境因素和遗传因素共同作用更易导致锰引起神经行为改变;携带Parkin基因7号外显子CC基因型的工人是锰损伤的易感者;Parkin基因7号外显子G951C突变导致Gly284Arg多态性有可能作为检测锰致神经行为改变以及锰中毒风险评估的指标.

Relationship between Neurobehavioral Changes and Exon 7 Polymorphism in Parkin Gene in MnExposed Workers

Objective ] To study the relationship between neurobehavioral changes and Parkin gene polymorphism in workers exposed to Mn. Methods ] A group of 200 Mn exposed workers having working age ≥ 0.5 year were assigned as high exposure or low exposure group according to their Mn cumulative exposure index （CEI）, and another 94 workers without Mn exposure were treated as controls. Every worker was evaluated by groove type steadiness test and pegboard test for neurobehavioral changes. The genetic DNA was extracted from every worker, and the genotypes of exon 7 polymorphism were detected by polymerase chain reaction- restriction fragment length polymorphism （PCR-RFLP）. Results ] In the high exposure group, the subjects with CC genotype of exon 7 were significantly lower in the length of drawing and the scores of pegboard test than those with GG and GC genotypes （P〈 0.05）; however, their collision frequencies were significantly higher （P〈 0.05）. In the low exposure group, the subjects with CC genotype of exon 7 were also significantly lower in the length of drawing and the scores of pegboard test than those with GG and GC genotypes （P〈 0.05）, but there was no significant difference in the collision frequency （P 〉 0.05）. In the control group, no significant difference in the neurobehavioral performances were found among subjects with different genotypes of exon 7 （P 〉 0.05）. Conclusion ] The combined effect of environmental and genetic factors may contribute to the neurobehavioral changes induced by Mn. Workers with CC genotype of exon 7 are susceptible to health impacts induced by Mn. The Gly284Arg polymorphism of exon 7 of Parkin gene shows the potential to be an indicator for manganese induced neurobehavioral changes and for risk assessment of manganese poisoning.