半乳糖血症患儿半乳糖-1-磷酸尿苷酰转移酶基因突变的鉴定与分析  

Identification and analysis of galactose-l-phosphate uridyltransferase gene mutations in children with galacto- semia

作　　者：王宇阳[1] 刘哲伟[1] 常会波[1] 王立文[1] 吴建新[1] 

机构地区：[1]首都儿科研究所附属儿童医院内科,100020

出　　处：《中华实用儿科临床杂志》2013年第8期603-605,共3页Chinese Journal of Applied Clinical Pediatrics

摘　　要：目的从分子水平研究半乳糖血症患儿半乳糖-1-磷酸尿苷酰转移酶基因（GALT基因）突变情况。方法选取2例确诊为半乳糖血症的患儿，分离其外周血淋巴细胞，提取总RNA，RT—PCR扩增GALT基因全长cDNA；将PCR产物亚克隆至T—easy载体，筛选阳性克隆并测序；同时，采用限制性片段多态性的方法将PCR产物进行酶切鉴定。结果2例患儿均出现了未报道过的突变。其中1例患儿GALT基因1006位A突变为G，导致M336V氨基酸突变；另1例患儿GALT基因779位A突变为T，导致H260L突变。这2例突变均为碱基替换形成的错义突变，且均为杂合型突变。结论基因诊断可提高半乳糖血症诊断的准确性，并为该病的产前筛查、造血干细胞移植甚至基因治疗提供有价值的参考。Objective To investigate the mutation of galactose-l-phosphate uridyhransferase gene （GALT gene） of galactosemia children by molecular methods. Methods Two children with galactosemia were investigated. The peripheral blood mononuclear ceils were separated and total RNA was extracted. Then,whole cDNAs of GALT were am- plified by reverse-transcription polymerase chain reaction;The PCR products were subcloned into T-easy vector and the positive clones were selected and sequenced;meanwhile, the PCR products were also digested by restricted enzymes and identified by restriction fragment length polymorphism. Results Two novel mutations were found in 2 children. In one child,A was changed into G in nucleotide 1006 of GALT gene,which led to amino acid residue M336V mutation. In the other child,A in nucleotide 779 of GALT gene was changed into T and led to amino acid residue H260L mutation. The 2 mutations were both missense mutation and heterozygous mutation. Conclusions Gene diagnosis is an useful method to improve the accuracy of galactosemia diagnosis and will provide valuable references for prenatal diagnosis, hemato- poietic stem cell transplantation and gene therapy.

关 键 词：半乳糖血症 半乳糖-1-磷酸尿苷酰转移酶 基因突变 

分 类 号：R72[医药卫生—儿科]