Allen M G
Arch Gen Psychiatry. 1976 Dec;33(12):1476-8. doi: 10.1001/archpsyc.1976.01770120080008.
In a summary of the major twin studies of affective illness, there are significant differences between monozygotic (MZ) and dizygotic (DZ) concordance rates for both unipolar and bipolar illness, indicating the importance of genetic factors in the etiology of affective illness. However, since 28% of MZ twins are discordant for bipolar illness and 60% of MZ twins are discordant for unipolar illness, environmental factors are important as well. In addition, there is a significant difference between unipolar and bipolar concordance for MZ twins (although not for DZ twins). This supports other evidence that unipolar and bipolar illness are separate entities, and it suggests the possibility that genetic factors are more important in the occurrence of bipolar illness than in unipolar illness.
在对情感性疾病的主要双胞胎研究总结中，单卵双胞胎（MZ）和双卵双胞胎（DZ）在单相和双相情感障碍的一致率上存在显著差异，这表明遗传因素在情感性疾病病因学中的重要性。然而，由于28%的单卵双胞胎在双相情感障碍上不一致，60%的单卵双胞胎在单相情感障碍上不一致，环境因素同样重要。此外，单卵双胞胎在单相和双相情感障碍的一致率之间存在显著差异（双卵双胞胎则不存在）。这支持了其他证据，即单相和双相情感障碍是不同的疾病实体，也表明遗传因素在双相情感障碍的发生中比在单相情感障碍中更重要。
