CAJ | 학술논문

目的识别房间隔缺损患者新的分子遗传缺陷.方法收集180例房间隔缺损患者的临床资料和血液标本.以200名健康者作为对照.应用聚合酶链反应扩增GATA4基因的全部外显子,采用双脱氧核苷链末端合成终止法对全部扩增片段进行测序.借助BLAST程序将所测序列与GenBank中的已知序列进行比对以识别基因突变,并用Clustal W软件分析突变氨基酸的保守性.结果在2例房间隔缺损患者的GATA4基因中各识别出1个新的杂合错义突变,即第21和第87位的密码子分别由GGC和CCG变为GTC和TCG,导致第21和87位的氨基酸分别由甘氨酸和脯氨酸变为缬氨酸和丝氨酸,即G21V和P87S突变.而健康者GATA4基因中未识别出这2个突变.多物种GATA4序列比对显示,突变氨基酸在进化上均高度保守.此外,还识别出1个不改变氨基酸的单核苷酸多态,即c.99 G＞T多态,但是ASD患者与健康者之间基因型和等位基因频率分布差异无统计学意义(GG比GT,x2=0.7556,P=0.3847;G比T,x2=0.7235,P=0.3950).结论识别出新的GATA4基因杂合错义突变,有助于房间隔缺损的早期防治.
목적 식별방간격결손환자신적분자유전결함.방법 수집180례방간격결손환자적림상자료화혈액표본.이200명건강자작위대조.응용취합매련반응확증GATA4기인적전부외현자,채용쌍탈양핵감련말단합성종지법대전부확증편단진행측서.차조BLAST정서장소측서렬여GenBank중적이지서렬진행비대이식별기인돌변,병용Clustal W연건분석돌변안기산적보수성.결과 재2례방간격결손환자적GATA4기인중각식별출1개신적잡합착의돌변,즉제21화제87위적밀마자분별유GGC화CCG변위GTC화TCG,도치제21화87위적안기산분별유감안산화포안산변위힐안산화사안산,즉G21V화P87S돌변.이건강자GATA4기인중미식별출저2개돌변.다물충GATA4서렬비대현시,돌변안기산재진화상균고도보수.차외,환식별출1개불개변안기산적단핵감산다태,즉c.99 G＞T다태,단시ASD환자여건강자지간기인형화등위기인빈솔분포차이무통계학의의(GG비GT,x2=0.7556,P=0.3847;G비T,x2=0.7235,P=0.3950).결론 식별출신적GATA4기인잡합착의돌변,유조우방간격결손적조기방치.
Objective To identify the genetic defects in patients with congenital atrial septal defects(ASD). Methods The clinical data and blood samples from 180 unrelated subjects with congenital ASD were collected and evaluated. Two hundred healthy individuals served as controls. The coding exons and the flanking introns of GATA4 gene were amplified by polymerase chain reaction and sequenced using the dideoxynucleotide chain termination approach. The acquired sequences were aligned with the sequences publicized in GenBank by the aid of programme BLAST to identify the sequence variations. Clustal W software was applied for analysis of the conservation of altered amino acids. Results Two novel heterozygous missense GATA4 mutations were identified in 2 out of 180 ASD patients. Namely, the triplet substitutions of GTC for GGC at codon 21 and TCG for CCG at codon 87 were detected, predicting the conversions of glycine into valine at amino acid residue 21(G21V)and proline into serine at amino acid residue 87(P87S). None of the two mutations were detected in 200 healthy controls. Across-species alignment of GATA4 encoded protein sequences displayed that the mutated amino acids were highly conserved evolutionarily. Additionally,a single nucleotide polymorphism c. 99G ＞ T was observed. However, the polymorphic frequency distribution in ASD cases was similar with that in healthy controls(for genotype GT, x2 = 0.7556, P = 0. 3847; for allele T, x2 = 0.7235, P = 0.3950). Conclusions Two novel mutations of GATA4 gene are identified in two unrelated ASD patients. This finding provides new insight into the molecular etiology responsible for ASD.