Yu Qing, Shen Yuan, Chatterjee Bishwanath, Siegfried Brett H, Leatherbury Linda, Rosenthal Julie, Lucas John F, Wessels Andy, Spurney Chris F, Wu Ying-Jie, Kirby Margaret L, Svenson Karen, Lo Cecilia W
Laboratory of Developmental Biology, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892-8019, USA.
Development. 2004 Dec;131(24):6211-23. doi: 10.1242/dev.01543. Epub 2004 Nov 17.
We used non-invasive high frequency ultrasound to screen N-ethyl-N-nitrosourea mutagenized mouse fetuses for congenital cardiovascular anomalies. We ultrasound scanned 7546 mouse fetuses from 262 mutagenized families, and identified 124 families with cardiovascular defects. Represented were most of the major congenital cardiovascular anomalies seen clinically. The ENU-induced mutations in several families were mapped using polymorphic microsatellite DNA markers. One family with forelimb anomalies and ventricular septal defects, phenotypes similar to Holt-Oram syndrome, and one family with transposition of the great arteries and heart situs anomalies were mapped to different regions of mouse chromosome 4. A third mutation causing persistent truncus arteriosus and craniofacial defects, phenotypes reminiscent of DiGeorge syndrome, was mapped to mouse chromosome 2. We note that mouse chromosomes 4 and 2 do not contain Tbx5 or Tbx1, genes previously linked to Holt-Oram and DiGeorge syndromes, respectively. In two other families, the ENU-induced mutation was identified--Sema3CL605P was associated with persistent truncus arteriosus with interrupted aortic arch, and the Gja1W45X connexin43 mutation caused conotruncal malformation and coronary aneurysms. Although our screen was designed as a recessive screen, a number of the mutations showed cardiovascular phenotypes in both heterozygote and homozygote animals. These studies show the efficacy of ENU mutagenesis and high-throughput ultrasound phenotyping in recovering mutations causing a wide spectrum of congenital heart defects. These ENU-induced mutations hold promise in yielding new insights into the genetic basis for human congenital heart disease.
我们使用非侵入性高频超声对经N-乙基-N-亚硝基脲诱变的小鼠胎儿进行先天性心血管异常筛查。我们对来自262个诱变家族的7546只小鼠胎儿进行了超声扫描，识别出124个有心血管缺陷的家族。临床所见的大多数主要先天性心血管异常均有体现。利用多态性微卫星DNA标记对几个家族中ENU诱导的突变进行了定位。一个有前肢异常和室间隔缺损（其表型与 Holt-Oram 综合征相似）的家族，以及一个有大动脉转位和心脏位置异常的家族，被定位到小鼠4号染色体的不同区域。第三个导致永存动脉干和颅面缺陷（其表型让人联想到DiGeorge综合征）的突变，被定位到小鼠2号染色体。我们注意到，小鼠4号和2号染色体分别不包含先前与Holt-Oram和DiGeorge综合征相关的Tbx5或Tbx1基因。在另外两个家族中，识别出了ENU诱导的突变——Sema3CL605P与永存动脉干伴主动脉弓中断有关，而Gja1W45X连接蛋白43突变导致圆锥动脉干畸形和冠状动脉瘤。尽管我们的筛查设计为隐性筛查，但许多突变在杂合子和纯合子动物中均表现出心血管表型。这些研究表明ENU诱变和高通量超声表型分析在发现导致广泛先天性心脏缺陷的突变方面的有效性。这些ENU诱导的突变有望为深入了解人类先天性心脏病的遗传基础带来新的见解。
