α_1-抗胰蛋白酶(α_1-AT)的缺乏与早发性慢性阻塞性肺部疾患的高发风险有关,Pizz表型者常患此病。伴有Pizz型的儿童,早期重症进行性肝病的风险约为7%;如果先证者有重症肝病,再生的Pizz型儿童患本病的风险将达40%,甚至更高。作者发现,限制性内切酶MaeⅢ能提供产前诊断所用的多态现象,除了Z蛋白342位上谷氨酸替代赖氨酸外,还有213位上缬氨 The lack of α 1-antitrypsin (α 1-AT) is associated with a high risk of premature chronic obstructive pulmonary disease, a condition frequently seen in the Pizz phenotype. Children with Pizz type have an early risk of severe progressive liver disease of about 7%, and if the proband has severe liver disease, the risk of developing this disease is 40% or more for children with Pizz. The authors found that the restriction endonuclease Mae III provides a polymorphism for prenatal diagnosis, in addition to glutamic acid at position 342 instead of lysine, valine at position 213