Wetmur J G, Lehnert G, Desnick R J
Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029.
Environ Res. 1991 Dec;56(2):109-19. doi: 10.1016/s0013-9351(05)80001-5.
The erythrocyte delta-aminolevulinate dehydratase (ALAD) isozyme phenotypes and the blood lead levels were determined in a population of 202 lead factory workers in Germany and an environmentally exposed population of 1278 children in New York who had elevated free protoporphyrin levels. In both population, individuals with the ALAD 1-2 or 2-2 isozyme phenotype had levels of blood lead statistically higher than those individuals with the ALAD 1-1 isozyme phenotype (lead workers: P greater than 0.004; children: P greater than 0.0001). Homozygotes and heterozygotes for the ALAD2 allele who expressed the 2-2 or 1-2 isozyme phenotype had median blood lead levels that were about 9 to 11 micrograms/dl greater than similarly exposed individuals who were homozygous for the ALAD1 allele. These findings support the hypothesis that the ALAD2 polypeptide binds lead more effectively, and therefore that individuals with the ALAD2 allele may be more susceptible to lead poisoning.
对德国202名铅厂工人以及纽约1278名游离原卟啉水平升高的环境暴露儿童群体，测定了红细胞δ-氨基乙酰丙酸脱水酶（ALAD）同工酶表型和血铅水平。在这两个群体中，具有ALAD 1-2或2-2同工酶表型的个体，其血铅水平在统计学上高于具有ALAD 1-1同工酶表型的个体（铅厂工人：P>0.004；儿童：P>0.0001）。表达2-2或1-2同工酶表型的ALAD2等位基因纯合子和杂合子，其血铅水平中位数比同样暴露的ALAD1等位基因纯合个体高约9至11微克/分升。这些发现支持了以下假说：ALAD2多肽与铅结合更有效，因此携带ALAD2等位基因的个体可能更容易发生铅中毒。
