临床遗传学作为专门学科的问世,使得很多过去未能明确区分的出生缺陷和综合征,得以阐明。它们中间,有些是单基因的,多器官受累则是不同组织中突变基因作的造成的。有些病例查悉是染色体缺陷或己知致畸剂(如苯妥因)造成出生缺陷的。但最常见的情况则是:既未发现特定遗传原因,亦未找到环境因素。临床遗传学发展迅速,大多数内科医生对很多新报道的综合征都不熟悉。虽然这些情况大多是在婴幼儿时期表现出来,但有些 The advent of clinical genetics as a specialized subject led to the clarification of many birth defects and syndromes that had not been clearly distinguished in the past. Among them, some are single-gene, and multiple organ involvement is caused by the mutated genes in different tissues. In some cases, chromosomal defects or known teratogenic agents (such as phenytoin) cause birth defects. However, the most common situation is that neither specific genetic causes nor environmental factors have been found. The rapid development of clinical genetics, most physicians are not familiar with many newly reported syndromes. Although most of these situations are manifested in infancy, some are