[Relationship between XRCC3 gene polymorphism and susceptibility to lead poisoning in male lead-exposed workers].

OBJECTIVE: To investigate the relationship between genetic polymorphism of X-ray repair cross-complementing gene 3 (XRCC3) and susceptibility to lead poisoning in male lead-exposed workers. METHODS: Peripheral venous blood and morning urine samples were collected from 326 male lead-exposed workers in a storage battery factory in Fuzhou. Blood lead, urine lead, blood zinc protoporphyrin (ZPP), blood calcium, and blood iron were measured. The genotype of XRCC3 was determined by polymerase chain reaction-restriction fragment length polymorphism method. The relationship between XRCC3 gene polymorphism and susceptibility to lead poisoning in male lead-exposed workers was analyzed. RESULTS: Genetic polymorphism of XRCC3 was seen in the 326 subjects. The frequency distribution of XRCC3 genotypes, XRCC3-241CC (wild type), XRCC3-241CT (heterozygous mutation), and XRCC3-241TT (homozygous mutation), was in accordance with the Hardy-Weinberg equilibrium (P > 0.05). There were no significant differences in urine lead, blood ZPP, blood calcium, and blood iron between the lead-exposed workers with different XRCC3 genotypes (P > 0.05). The workers with XRCC3-241CT/TT had a significantly higher mean blood lead level than those with XRCC3-241CC (P < 0.05). With a blood lead level of 1.90 µmol/L as the cutoff value, the chi-square test and logistic regression analysis showed that the proportion of workers with XRCC3-241CT/TT was significantly higher than that of workers with XRCC3-241CC in the subjects with high blood leads (P < 0.05) and that the risk of high blood lead was significantly higher in the workers with XRCC3-241CT/TT than in those with XRCC3-241CC (OR = 2.34, 95%CI = 1.61 ∼ 5.13); the multivariate linear regression analysis showed that the workers with XRCC3-241CT/TT had high blood lead levels (ß = 0.116, P < 0.05), the workers with smoking habit demonstrated marked lead absorption (ß = 0.188, P < 0.05), good individual protection could reduce lead absorption (ß = -0.247, P < 0.05), and the individuals with low serum Ca²âº levels had high blood lead levels (ß = -0.145, P < 0.05). CONCLUSION: When exposed to the same level of lead at workplace, the workers with XRCC3-241CT/TT have a significantly higher blood lead level than those with XRCC3-241CC, so the genotype of XRCC3-241CT/TT accounts for higher susceptibility to lead poisoning.

[AFLP analysis in populations of Strongylocentrotus intermedius, S. nudus and hybrids (S. intermedius x S. nudus)].

AFLP analysis of genetic diversity in the three populations of sea urchin Strongylocentrotus intermedius (IN), S. nudus (NU) and F1 progeny (INxNU) was carried out in this paper. In total, 272 loci were amplified with 4 primer pairs, of which 269 were polymorphic and the percentage of polymorphic loci was 98.89%. The Shannon diversity index for S. intermedius, S. nudus, and their hybrid populations was 0.2331+/-0.1273, 0.2005+/-0.1385, and 0.2625+/-0.1067, respectively. The genetic similarity within populations was 0.6876+/-0.0523, 0.6501+/-0.0548, and 0.6552+/-0.0553, respectively. AMOVA analysis indicated that 25.39% of variance was among populations and 74.61% of variance was within populations. This suggested the rich genetic diversity level within populations. Although the hybrids can be classified into two types by apparent characters, they were clustered each other by UPGMA method according to their genetic distances.