Eley T C, Deater-Deckard K, Fombonne E, Fulker D W, Plomin R
Institute of Psychiatry, London, U.K.
J Child Psychol Psychiatry. 1998 Mar;39(3):337-45.
Several twin studies of children and adolescents have found significant heritability of depressive symptoms. In contrast, the sole adoption study of biologically related and biologically unrelated adopted siblings found no evidence for genetic influence. The present study attempts to confirm these results in middle childhood using two adoption designs. The sample, from the Colorado Adoption Project, included 180 adopted children (77 with adoptive siblings) and their biological and adoptive mothers, and 227 nonadopted children (93 with biological siblings) and their mothers. Mothers reported their own neuroticism, and children's depressive symptoms were reported by the parents and by the children themselves. For both the sibling adoption and the parent-offspring designs heritability was negligible, shared environment modest, and non-shared environment substantial, irrespective of child gender. Although the power of the sibling data is low, the combined findings from the two designs suggest that genetic effects on depressive symptoms in childhood may be somewhat smaller than previously estimated in twin studies.
多项针对儿童和青少年的双胞胎研究发现，抑郁症状具有显著的遗传力。相比之下，唯一一项对有血缘关系和无血缘关系的养兄弟姐妹进行的收养研究未发现遗传影响的证据。本研究试图采用两种收养设计来证实童年中期的这些结果。样本来自科罗拉多收养项目，包括180名被收养儿童（77名有养兄弟姐妹）及其亲生母亲和养母，以及227名非收养儿童（93名有亲兄弟姐妹）及其母亲。母亲们报告了自己的神经质情况，父母和孩子们自己报告了孩子的抑郁症状。对于兄弟姐妹收养设计和亲子设计而言，无论孩子性别如何，遗传力都可忽略不计，共享环境影响适中，非共享环境影响较大。尽管兄弟姐妹数据的效力较低，但两种设计的综合结果表明，童年期遗传因素对抑郁症状的影响可能比之前在双胞胎研究中估计的要小一些。
