Becker T A, Van Amber R, Moller J H, Pierpont M E
Ray & Hattie Anderson Center, Department of Pediatrics, University of Minnesota, Minneapolis, USA.
Am J Med Genet. 1996 Dec 2;66(1):28-32. doi: 10.1002/(SICI)1096-8628(19961202)66:1<28::AID-AJMG7>3.0.CO;2-S.
Transposition of the great arteries (TGA) is the most common cyanotic cardiac malformation, representing 5-7% of all cardiac malformations. Previous estimates of the frequency of cardiac malformations in sibs of probands range from 0-1.7%. This study ascertained the frequency of congenital cardiac malformations in relatives of 271 probands with TGA, who were grouped according to the type of TGA present. These include dextro (d-TGA), levo (l-TGA), complex TGA, and asplenia with TGA. In the d-TGA cases there were 369 sibs, one of whom had a cardiac malformation (0.27%). There were 50 sibs in the l-TGA group, with one sib having a cardiac malformation (2.00%). Cardiac malformations were found in 2 of 143 (1.40%) sibs of the complex TGA index cases, and 1 of 50 (2.00%) sibs in the asplenia with TGA group. The overall recurrence risk of cardiac malformations in sibs of TGA probands was 0.82%. Cardiac malformations in parents of probands were found in 0.29% of d-TGA, 0% of l-TGA, 1.54% of complex TGA, and 0% of asplenia with TGA, giving an overall parental occurrence of 0.55%. This is the first study to provide information on the different types of TGA in evaluating sib occurrence. It provides necessary genetic counseling information for families of probands with TGA.
大动脉转位（TGA）是最常见的青紫型心脏畸形，占所有心脏畸形的5%-7%。先前对先证者同胞中心脏畸形发生率的估计范围为0%-1.7%。本研究确定了271例TGA先证者亲属中先天性心脏畸形的发生率，这些先证者根据所患TGA的类型进行分组。这些类型包括右旋（d-TGA）、左旋（l-TGA）、复杂型TGA以及合并无脾畸形的TGA。在d-TGA病例组中有369名同胞，其中1名患有心脏畸形（0.27%）。l-TGA组中有50名同胞，其中1名患有心脏畸形（2.00%）。复杂型TGA指数病例的143名同胞中有2名（1.40%）患有心脏畸形，合并无脾畸形的TGA组的50名同胞中有1名（2.00%）患有心脏畸形。TGA先证者同胞中心脏畸形的总体复发风险为0.82%。先证者父母中，d-TGA组心脏畸形发生率为0.29%，l-TGA组为0%，复杂型TGA组为1.54%，合并无脾畸形的TGA组为0%，父母总体发生率为0.55%。这是第一项在评估同胞发生率时提供不同类型TGA相关信息的研究。它为先证者患有TGA的家庭提供了必要的遗传咨询信息。
