OBJECTIVETo explore association genetic polymorphism of XPD with chromosomal damage in workers exposed to radiation.

METHODS182 workers exposed to radiation for at least one year with chromosomal damage were selected as cases based on a general health examination for all workers exposed to radiation in Tangshan city. The control group without chromosomal damage was matched to case by age (within 5 years), sex, work unit, type of exposed to radiation, cumulate serve length (within 1 year) according to 1:1. The micro whole blood cultivation was used for the chromosome analysis. The chromosome aberration type and rate were observed and counted. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine the genotype of three XPD loci (751, 312 and 156).

RESULTSThe frequency of XPD 751 AA in cases was higher than that in controls (P < 0.05). The frequency of 751 allele in case group was statistically higher than that in the control groups (P < 0.05). No statistical difference was found in the frequencies of XPD 312 genotype and allele between the case and control group (P > 0.05). 156 mutant gene type in case group was higher than that in the control groups. The frequency of 156 A allele in case group were higher than that of the control groups (P < 0.05). The frequency of genotype with both 751AA and 156CA or 751AA and 156AA was higher in cases than that of controls (P < 0.05).

CONCLUSIONXPD 751AA genotype is a possible risk factor for radiation-induced chromosomal damage. XPD 156 mutant gene type is a possible risk factor for radiation-induced chromosomal damage. Individuals with both XPD 751AA and 156 (CA+AA) genotypes are susceptible to radiation-induced chromosomal damage. No association of XPD 312 polymorphism with radiation-induced chromosomal damage is found.