Predominantly global genetic influences on individual white matter tract microstructure
Predominantly global genetic influences on individual white matter tract microstructure
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DOI：
10.1016/j.neuroimage.2018.10.016
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发表时间：
2019-01-01
期刊：
影响因子：
5.7
通讯作者：
Kremer, William S.
中科院分区：
文献类型：
--
作者：
Gustayson, Daniel E.;Hatton, Sean N.;Kremer, William S.
用扩散张量成像（DTI）测量的白色束微结构的个体差异显示了显著的遗传性。然而，目前还不清楚这种遗传力在多大程度上反映了全球遗传影响或特定区域的遗传影响。本研究的目的是量化的遗传和环境方差的比例在白色物质束归因于全球与特定的影响。我们评估了部分各向异性（FA），平均扩散率（MD），轴向扩散率（AD），径向扩散率（RD）在11个道和这些道的22个细分在392个中年男性双胞胎从越南时代双胞胎老化研究（VETSA）。在主成分分析的11个白色物质束，第一个组成部分，这代表了全球的信号，解释50.1%和62.5%的方差FA和MD，分别。同样，第一主成分的22道细分解释38.4%和47.0%的方差FA和MD，分别。双胞胎建模显示，所有的道和细分的DTI措施是可遗传的，和全球FA和MD的遗传影响占约一半的遗传力的道或道细分。对于AD和RD扩散度量观察到类似的结果。这些发现强调了在测量特定的神经束与认知能力、神经和精神疾病以及大脑老化等结果之间的关联时，控制DTI全局信号的重要性。
Individual differences in white matter tract microstructure, measured with diffusion tensor imaging (DTI), demonstrate substantial heritability. However, it is unclear to what extent this heritability reflects global genetic influences or tract-specific genetic influences. The goal of the current study was to quantify the proportion of genetic and environmental variance in white matter tracts attributable to global versus tract-specific influences. We assessed fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) across 11 tracts and 22 subdivisions of these tracts in 392 middle-aged male twins from the Vietnam Era Twin Study of Aging (VETSA). In principal component analyses of the 11 white matter tracts, the first component, which represents the global signal, explained 50.1% and 62.5% of the variance in FA and MD, respectively. Similarly, the first principal component of the 22 tract subdivisions explained 38.4% and 47.0% of the variance in FA and MD, respectively. Twin modeling revealed that DTI measures of all tracts and subdivisions were heritable, and that genetic influences on global FA and MD accounted for approximately half of the heritability in the tracts or tract subdivisions. Similar results were observed for the AD and RD diffusion metrics. These findings underscore the importance of controlling for DTI global signals when measuring associations between specific tracts and outcomes such as cognitive ability, neurological and psychiatric disorders, and brain aging.