CAJ | 학술논문

目的确定ankyrin-B基因突变在日本人群QT间期延长综合征中的发病率以及ankyrin-B基因突变与QT间期延长综合征之间的关系.方法我们对相互之间无血缘关系的日本人群已确诊的QT间期延长综合征患者78例(男28例,女50例)进行了研究.在征得患者的同意之后,从其白细胞中提取纯化基因组DNA并行多聚酶链式反应(PCR)扩增.随即对扩增的DNA行单链构像多态性(SSCP)分析.而后将突变或异常的SSCP产物分离后,采用自动荧光测序仪检测DNA序列.最后再用150例正常健康人的DNA作为对照,对上述经测序确认的误义点突变进行PCR-限制性片段长度多态性分析,以进一步证实误义点突变的真实性和可靠性.结果我们在一例确诊的QT间期延长综合征患者的ankyrin-B基因的4603碱基位点上发现了从T到A的突变(T4603A).出现于基因的第40号外显子上的该误义点突变,导致了氨基酸序列第1535位点上的色氨酸残基被精氨酸残基所取代(W1535R).而该氨基酸序列正位于ankyrin-B基因高度保守的调节区域.结论新发现的位于ankyrin-B基因调节区域的误义点突变可能是导致4型QT间期延长综合征的原因之一,而该突变似乎并不是导致日本人群4型QT间期延长综合征的主要病因.
목적학정ankyrin-B기인돌변재일본인군QT간기연장종합정중적발병솔이급ankyrin-B기인돌변여QT간기연장종합정지간적관계.방법아문대상호지간무혈연관계적일본인군이학진적QT간기연장종합정환자78례(남28례,녀50례)진행료연구.재정득환자적동의지후,종기백세포중제취순화기인조DNA병행다취매련식반응(PCR)확증.수즉대확증적DNA행단련구상다태성(SSCP)분석.이후장돌변혹이상적SSCP산물분리후,채용자동형광측서의검측DNA서렬.최후재용150례정상건강인적DNA작위대조,대상술경측서학인적오의점돌변진행PCR-한제성편단장도다태성분석,이진일보증실오의점돌변적진실성화가고성.결과아문재일례학진적QT간기연장종합정환자적ankyrin-B기인적4603감기위점상발현료종T도A적돌변(T4603A).출현우기인적제40호외현자상적해오의점돌변,도치료안기산서렬제1535위점상적색안산잔기피정안산잔기소취대(W1535R).이해안기산서렬정위우ankyrin-B기인고도보수적조절구역.결론신발현적위우ankyrin-B기인조절구역적오의점돌변가능시도치4형QT간기연장종합정적원인지일,이해돌변사호병불시도치일본인군4형QT간기연장종합정적주요병인.
Objectives To identify the ankyrin-B gene mutations that cause long QT syndrome (LQTS) and determine the prevalence of such mutations in Japanese patients with LQTS. Methods We conducted a search for ankyrin-B gene mutation in 78 unrelated patients with LQTS (28 males and 50 females, aged 2 to 89 years). With informed consent from all the subjects and/or their parents, genomic DNA was purified from the white blood cells of the patients and amplified using polymerase chain reaction (PCR). Single-strand conformational polymorphism (SSCP) analysis of the amplified DNA was performed to screen for mutations and aberrant SSCP products were isolated and sequenced by dye terminator cycle sequencing method using an automated fluorescent sequencer. PCR and restriction fragment length polymorphism (PCR-RFLP) analysis was carried out to further confirm the missense mutations by comparison with samples from 150 normal healthy individuals.Results We identified a T to A transition mutation at position 4 603 in exon 40, resulting in the substitution of arginine for a tryptophan at amino acid residue 1 535 (W1535R) in the regulatory domain of 220-kD ankyrin-B, which is a highly conserved domain shared by different species. Conclusions This novel missense mutation in the ankyrin-B gene may bea cause of type 4LQTS. Ankyrin-B gene mutation might not play the major role in LQTS in Japanese.