Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada.
J Abnorm Psychol. 2010 Nov;119(4):672-82. doi: 10.1037/a0021132.
It is unknown whether various types of obsessive-compulsive (OC) symptoms have a common genetic or environmental etiology. For example, it is unknown whether hoarding is etiologically associated with prototypic OC symptoms, such as washing, checking, and obsessing. Also unknown is whether particular OC-related symptoms are etiologically linked to the general tendency to experience emotional distress (negative emotionality). To investigate these and other issues, a community sample of 307 pairs of monozygotic and dizygotic adult twins provided scores on 6 OC-related symptoms (obsessing, neutralizing, checking, washing, ordering, and hoarding) and 2 markers of negative emotionality (trait anxiety and affective lability). Genetic factors accounted for 40%-56% of variance in the 8 phenotypic scores (M = 49% of variance for OC-related symptoms). Remaining variance was due to nonshared (person-specific) environment. More detailed analyses revealed a complex etiologic architecture, where OC-related symptoms arise from a mix of common and symptom-specific genetic and environmental factors. A general genetic factor was identified, which influenced all symptoms and negative emotionality. An environmental factor was identified that influenced all symptoms but did not influence negative emotionality. Each of the 6 types of symptoms was also shaped by its own set of symptom-specific genetic and environmental factors. The importance of genetic factors did not vary as a function of age or sex, and the architecture of general and specific etiologic factors was replicated for participants having relatively more severe OC symptoms. Gene-environment interactions were identified. Implications for an etiology-based classification system are discussed.
目前尚不清楚各种类型的强迫症（OC）症状是否具有共同的遗传或环境病因。例如，囤积是否与典型的 OC 症状（如洗涤、检查和痴迷）在病因学上有关尚不清楚。也不知道特定的 OC 相关症状是否与经历情绪困扰（负性情绪）的一般倾向在病因学上有关。为了研究这些和其他问题，一个由 307 对同卵和异卵双胞胎组成的社区样本提供了 6 种 OC 相关症状（痴迷、中和、检查、洗涤、排序和囤积）和 2 种负性情绪指标（特质焦虑和情感不稳定性）的得分。遗传因素解释了 8 个表型得分的 40%-56%的变异（OC 相关症状的平均值为 56%的变异）。其余的变异是由非共享（个体特定）环境造成的。更详细的分析揭示了一个复杂的病因结构，其中 OC 相关症状来自共同和症状特异性遗传和环境因素的混合。确定了一个一般的遗传因素，它影响所有的症状和负性情绪。确定了一个环境因素，它影响所有的症状，但不影响负性情绪。6 种类型的症状中的每一种都受到其自身的一组症状特异性遗传和环境因素的影响。遗传因素的重要性不因年龄或性别而异，并且对于 OC 症状相对更严重的参与者，一般和特定病因因素的结构是可复制的。确定了基因-环境相互作用。讨论了基于病因的分类系统的意义。
