Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive (MC 0738), La Jolla, CA 92093, USA.
Neuroimage. 2010 Jan 15;49(2):1213-23. doi: 10.1016/j.neuroimage.2009.09.043. Epub 2009 Sep 26.
The impact of genetic and environmental factors on human brain structure is of great importance for understanding normative cognitive and brain aging as well as neuropsychiatric disorders. However, most studies of genetic and environmental influences on human brain structure have either focused on global measures or have had samples that were too small for reliable estimates. Using the classical twin design, we assessed genetic, shared environmental, and individual-specific environmental influences on individual differences in the size of 96 brain regions of interest (ROIs). Participants were 474 middle-aged male twins (202 pairs; 70 unpaired) in the Vietnam Era Twin Study of Aging (VETSA). They were 51-59 years old, and were similar to U.S. men in their age range in terms of sociodemographic and health characteristics. We measured thickness of cortical ROIs and volume of other ROIs. On average, genetic influences accounted for approximately 70% of the variance in the volume of global, subcortical, and ventricular ROIs and approximately 45% of the variance in the thickness of cortical ROIs. There was greater variability in the heritability of cortical ROIs (0.00-0.75) as compared with subcortical and ventricular ROIs (0.48-0.85). The results did not indicate lateralized heritability differences or greater genetic influences on the size of regions underlying higher cognitive functions. The findings provide key information for imaging genetic studies and other studies of brain phenotypes and endophenotypes. Longitudinal analysis will be needed to determine whether the degree of genetic and environmental influences changes for different ROIs from midlife to later life.
遗传和环境因素对人类大脑结构的影响对于理解正常认知和大脑衰老以及神经精神障碍非常重要。然而，大多数关于遗传和环境因素对人类大脑结构影响的研究要么集中在整体测量上，要么样本太小，无法进行可靠的估计。我们使用经典的双胞胎设计，评估了遗传、共享环境和个体特定环境对 96 个感兴趣脑区（ROI）大小的个体差异的影响。参与者是越南时代衰老双胞胎研究（VETSA）中的 474 名中年男性双胞胎（202 对；70 对非双胞胎）。他们年龄在 51-59 岁之间，在社会人口统计学和健康特征方面与美国同龄男性相似。我们测量了皮质 ROI 的厚度和其他 ROI 的体积。平均而言，遗传因素约占全球、皮质下和脑室 ROI 体积的 70%，皮质 ROI 厚度的 45%左右。皮质 ROI 的遗传变异性（0.00-0.75）大于皮质下和脑室 ROI 的遗传变异性（0.48-0.85）。结果并未表明大脑左右侧的遗传差异或对更高认知功能相关区域大小的遗传影响更大。这些发现为影像学遗传研究以及大脑表型和内表型的其他研究提供了关键信息。需要进行纵向分析，以确定不同 ROI 从中年到晚年的遗传和环境影响程度是否会发生变化。
