Objective: To study the relationship between the polymorphism of butyrylcholinesterase (BChE, EC 3.1.1.8) and paraoxonase (PonE, EC 3.1.8.1), and the individuals' genetic susceptibility to organophosphates pesticides (OPs) exposure.
Methods: 75 OPs exposure workers were selected to determine their BChE-K, PON-192 and PON-55 genotypes using PCR-RFLP. The accumulative symptom scores and the whole blood acetylcholinesterase activity (mmol x h(-1) x ml(-1)) were used as health index. Firstly, the health condition related to single gene site of the three gene loci was analyzed to determine which kinds of genotype were susceptible. Then, used the multiple variance analysis was to see if there existed interactions among these three gene loci. Finally, established the multi-factor linear regression equation, in which considered some other factors that might influence the health situation such as age, gender and the exposure time. According to the equation, could get the accumulative symptom scores of each kind of subpopulation of different genotypes.
Results: The mean AChE activities of the exposed workers with BChE-K genotype UU (61 cases), genotype UK (12 cases) and genotype KK (2 cases) were 105.0 +/- 23.0, 84.4 +/- 16.4, 79.0 +/- 9.9, respectively; The accumulative symptom scores were 3.7 +/- 3.8, 9.2 +/- 3.0, 12.5 +/- 0.7, respectively. The AChE activities of the exposed workers with PON-192 genotype BB (37 cases), genotype AB (27 cases) and genotype AA (11 cases) were 116.8 +/- 15.1, 91.2 +/- 15.6, 72.3 +/- 21.4, respectively; The accumulative symptom scores were 2.0 +/- 3.2, 6.7 +/- 3.3, 9.7 +/- 1.8, respectively. Similarly, the AChE activities of the exposed workers with PON-55 genotype LL (70 cases) and genotype LM (5 cases) were 102.4 +/- 23.0, 82.8 +/- 22.0; The accumulative symptom scores were 4.5 +/- 4.2, 9.2 +/- 3.6, respectively. Single variance analysis showed that the accumulative symptom scores of the individuals with abnormal homozygote of these three gene loci were the highest, which indicated that they were most susceptible to OPs. Multiple variance analysis showed there were no interactions among the three gene loci. Age, gender and exposure time had no statistical significance, while genotypes of the three gene loci had statistical significance to health situation.
Conclusion: Genotypes of BChE-K, PON-192 and PON-55 are related to susceptibility to OPs exposure.