A comprehensive study published recently in the journal of genetic counseling indicates such children run an only slightly higher risk of significant genetic disorders like congenital heart defects - - about two percentage points above the average 3 to 4 最近发表在《遗传学咨询》杂志上的一份综合性研究表明近亲婚姻所生的小孩患上主要遗传性疾病如先天性心脏缺陷的可能性只比一般小孩略高- -大约比平均的3到4高出两个百分点。
