Twin studies of affective illness.

@article{Allen1976TwinSO,
  title={Twin studies of affective illness.},
  author={Mark G. Allen},
  journal={Archives of general psychiatry},
  year={1976},
  volume={33 12},
  pages={1476-8}
}
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… CONTINUE READING