儿童哮喘α_1-抗糜蛋白酶遗传缺陷探索性研究

Hereditary α_1-Antichymotrypsin Deficiency in Childhood Asthma

目的 评估儿童哮喘α1 抗糜蛋白酶 (α1 ACT)杂合缺失频率及基因突变类型。方法 应用火箭免疫电泳技术对 90例哮喘儿童、195例健康儿童及 198例健康成人血浆α1 ACT含量进行检测 ;经家系调查确定 3组α1 ACT杂合缺失频率 ;分析了哮喘组α1 ACT杂合缺失和非杂合缺失患儿的有关临床资料 ;应用聚合酶链反应和限制性酶切图谱分析技术对 5例α1 ACT杂合缺失个体的α1 ACT基因外显子Ⅱ和Ⅲ进行了检测。结果 哮喘组、儿童对照组以及成人对照组α1 ACT杂合缺失频率依次为 4 .4 % ,0 ,0 .5 % ,哮喘组较儿童及成人对照组明显增高(P <0 .0 5 ) ;α1 ACT杂合缺失哮喘患儿初发年龄早、住院次数多、放射性过敏原吸附试验阳性率显著增高 (P <0 .0 1或 0 .0 5 )。基因分析未找到Bonn 1和Bochum 1变异体。结论 α1 ACT杂合缺失与儿童哮喘发病及其严重性存在一定的联系 ;Bonn 1和Bochum

Objective To investigate the frequency of heterozygous α 1 antichymotrypsin(α 1 ACT) deficiency and the types of gene mutation in childhood asthma. Methods The plasma level of α 1 ACT was detected using the rocket immunoelectrophoresis in 90 children with asthma (asthma group), 195 healthy children (normal children control group) and 198 healthy adults (normal adult control group). The frequency of heterozygous α 1 ACT deficiency was determined by studying the family history in the 3 groups. The clinic data of the children with or without heterozygous α 1 ACT deficiency were analyzed. Gene exon Ⅱ and exon Ⅲ were detected by PCR and restriction endonuclease mapping techniques in the 5 cases with heterozygous α 1 ACT deficiency. Results The frequency of heterozygous α 1 ACT deficiency in the asthma group ( 4.4% ) was markedly higher than that in the normal child control group (0) and the normal adult control group ( 0.5% ) (both P< 0.05 ). The age of the onset of asthma was smaller, the number of times of hospitalization for asthma were greater, and the positive rate of the radioactive allergen sensitive test was higher in the children with heterozygous α 1 ACT deficiency than those without deficiency (P< 0.05 or 0.01 ). No variants of Bonn 1 and Bochum 1 were found in the 5 cases with heterozygous α 1 ACT deficiency. Conclusions There is a possible association between heterozygous α 1 ACT deficiency and childhood asthma; the variants of Bonn 1 and Bochum 1 are not correlated with childhood asthma.