【摘要】 目的　Jervell Lange Nielsen综合征 (JLNS)是一种罕见的遗传性心脏、听觉异常综合征。表现为感觉神经性耳聋、QT间期延长、异常T波和室性心动过速 ,大多为常染色体隐性遗传。报道对一个JLNS家系KCNQ1基因扫描及发现其突变形式。方法　该家系成员共 13例 ,经仔细询问病史、体格检查、做同步 12导联心电图、超声心动图 ,采集静脉血标本 ,提取基因组DNA。PCR扩增KCNQ1基因各外显子及相邻内含子部分序列 ,直接测序分析筛查基因突变点。结果　发现家系中 6例KCNQ1发生单一杂合突变 ,第 917个核苷酸G变为T ,导致代表甘氨酸残基的第 30 6密码子突变为缬氨酸残基 (G30 6V) ,家系中正常人和 5 0例正常对照无此突变。结论　首次发现KCNQ1单一杂合突变导致JLNS ,提示不仅KCNQ1纯合突变和复合杂合突变能够导致JLNS ,而且KCNQ1单一杂合突变也可以导致JLNS。更多还原

【Abstract】 Objective Jervell and Lange-Nielsen syndrome(JLNS) is a severe cardioauditory syndrome manifested as QT interval prolongation,abnormal T waves, and relative bradycardia ventricular tachyarrhythmias.In this report, we screened a nonconsanguineous families with JLNS for mutations in KCNQ1. Methods Mutation analysis was performed by using purified PCR products to direct sequence analysis on an ABI-3730XL automated DNA sequencer. The whole sequence of proband′KCNQ1 was screened firstly, then screened the mutation exon sequences of others of the family and 50 unrelated normal persons. Results A heterogeneous mutation was identified in the patients of the JLNS family, a missense mutation(G→T) at nucleotide 917 encoded in exon 6 of KCNQ1 . This substitution leads to a change from glycine to Valine at codon 306(G306V)corresponding to the S5 transmembrane segment of KCNQ1.The other normal members of the family and 50 unrelated normal persons were not identified this mutation. Conclusion The result suggested that not only homozygous mutations or compound heterozygous mutations in KCNQ1 could cause Jervell-Lange-Nielsen syndrome,the single heterozygous mutation may also cause Jervell-Lange-Nielsen syndrome.更多还原