【作者】 田薇；

【导师】 陈艳；

【作者基本信息】 新疆医科大学 ， 卫生毒理学， 2008， 硕士

【摘要】 目的:了解维生素D受体基因FokⅠ多态性在汉族、维吾尔族及哈萨克族儿童中的分布,及与铅中毒遗传易感性的关系;并探讨儿童铅中毒的危险因素。方法:按照整群随机抽样的方法抽取乌鲁木齐市6-10岁的489名汉族、499名维族和525名哈族儿童,利用BH-2100光谱仪测定儿童血铅值,并应用聚合酶链式反应-限制性片断长度多态性(PCR-RFLP)技术,对维生素D受体基因FokⅠ位点多态性进行检测。结果:1 FF、Ff、ff 3种基因型在维族中分别占54%、38%、9%,哈族中占49%、45%、7%,汉族占38%、51%、11%;F、f等位基因分布频率在维族为72.4%、27.6%,哈族为70.9%、29.1%,汉族为63.4%、36.6%。基因型和等位基因的分布频率在维、汉民族间的差异有统计学意义(χ~2=21.90,P<0.05;χ~2=17.26,P<0.05),哈、汉民族间有统计学意义(χ~2=14.54,P<0.05;χ~2=13.43,P<0.05),而维、哈民族间无统计学意义(χ~2=4.75,P>0.05;χ~2=0.58,P>0.05)。2汉族儿童血铅均值为53.05±2.24μg/L,携带FF及Ff/ff基因型者的血铅均值分别为56.72±2.18μg/L、51.44±2.27μg/L;维族儿童血铅均值为55.87±2.23μg/L,携带FF及Ff/ff基因型者的血铅均值分别为56.88±2.21μg/L、54.18±2.34μg/L;哈族儿童血铅均值为61.24±1.90μg/L,携带FF及Ff/ff基因型者的血铅均值分别为63.77±1.82μg/L、58.12±1.98μg/L。但不同基因型血铅水平均无统计学意义。3儿童血铅均值为56.57±2.14μg/L,其流行率为22.87%。哈族儿童血铅值略高于维族、汉族儿童,但三者之间均无统计学意义。儿童年龄、父母文化程度、父母亲从事铅接触职业、不良生活习惯及家庭居住环境是影响儿童血铅水平的主要因素。结论:维生素D受体基因FokⅠ位点基因型及等位基因在不同种族间分布频率有差异,而在低水平铅暴露条件下,FokⅠ位点等位基因分布对儿童血铅无明显影响。儿童铅中毒与儿童生活居住环境因素、生活习惯、饮食习惯等多种因素有关。更多还原

【Abstract】 Objective: To investigate the polymorphism distribution of vitamin D receptor gene FokⅠsite and the relationship between polymorphism of FokⅠand lead poisoning, and to analyse the risk factors of lead poisoning among Han, Uygur and Kazak children. Methods: Cluster sampling was used to choose 489 Hans, 499 Uygurs and 525 Kazaks in Urumqi. Blood lead was determined by BH-2100 Atomic Absorption Spectrometer. Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method was used to analyze the genotype of VDR gene FokⅠsite.Results: 1 The frequencies of FF, Ff and ff genotypes were found to be 38%, 51%, 11% in the Hans , 54%, 38%, 9% in the Uygurs, and49%, 45%, 7% in the Kazaks; the frequencies of allele were found to be 63.4%, 36.6% in the Hans, 72.4%, 27.6% in the Uygurs, and 70.9%, 29.1% in the Kazaks. Significant differences were seen in the frequency distribution of VDR genotype and allele between the Uygurs and the Hans (χ~2=21.90,P<0.05;χ~2=17.26,P<0.05), and significant differences were seen in the frequency distribution of VDR genotype and allele between the Kazaks and the Hans (χ~2=14.54,P<0.05;χ~2=13.43,P<0.05). There were indifferences in the frequency distribution of VDR genotype and allele between the Uygurs and the Kazaks(χ~2=4.75,P>0.05;χ~2=0.58,P>0.05)2 The blood level of Han children were 53.05±2.24μg/L, the mean level of blood lead was 56.72±2.18μg/L in homozygous individuals with F allele, while the mean level of blood lead was 51.44±2.27μg/L in the heterozygous or homozygous with f allele; the blood level of Uygur children were 55.87±2.23μg/L, the mean level of blood lead was 56.88±2.21μg/L in homozygous individuals with F allele, while the mean value was 54.18±2.34μg/L in the heterozygous or homozygous with f allele; the mean level of blood lead of Kazak children were 61.24±1.90μg/L, the mean blood lead level was 63.77±1.82μg/L in homozygous individuals with F allele, while the mean value was 58.12±1.98μg/L in the heterozygous or homozygous with f allele. No statistic correlation between the distribution of FokⅠalleles and the level of blood lead was found in these three populations. 3 In our study, the mean level of blood lead of all of children was 56.57±2.14μg/L, the blood lead concentration of 22.87% of children was more than 100μg/L. The level of blood lead of Kazak children was the highest in the three nationalities, but there are no significances among them. It was the high-risk factors of children’s age, parents’education, parents’occupation, bad habits, housing condition, living environment were associated with level of blood lead. Conclusion: A significant difference was seen in the frequency distribution of VDR genotype and allele among the different races. The effect of FokⅠpolymorphism on blood lead levels may not exhibit significant difference in environmental exposured children.更多还原