基于磁共振影像的人脑结构偏侧化的遗传效应研究进展

Research progress on genetic effects of the asymmetry of human brain structure revealed by magnetic resonance imaging

偏侧化是人脑结构的基本特征,揭示偏侧化的遗传效应是阐明其发生机制的先决条件。多模态磁共振影像技术的发展为全面探测大脑偏侧化及其遗传机制提供了技术手段。通过结合磁共振影像数据,现已可以用基因-遗传度等方法对人脑结构偏侧化的个体差异进行定量遗传映射研究,而双生子模型为研究先天遗传和后天环境对大脑的影响提供了天然的试验模型。基于磁共振影像的双生子研究表明,人脑结构组织的偏侧化是有基因作为遗传基础的。本文以定量遗传分析为视角,着重从遗传度的偏侧化、偏侧化的遗传度及遗传相关性三大层面,回顾分析半脑偏侧化的基因效应及共变的基因机制研究的最新进展,并提出该领域发展的局限性和挑战。这一系统的回顾旨在快速地引导科研人员了解人脑左右半球差异的起源与遗传机制的研究现状,为进一步理解和探讨偏侧的认知行为个体差异提供了遗传依据。

Hemispheric asymmetry is a fundamental organizing principle of the human brain.Answering the genetic effects of the asymmetry is a prerequisite for elucidating developmental mechanisms of brain asymmetries.Multimodal magnetic resonance imaging(MRI)has provided an important tool for comprehensively interpreting human brain asymmetry and its genetic mechanism.By combining MRI data,individual differences in brain structural asymmetry have been investigated with quantitative genetic brain mapping using gene-heritability.Twins provide a useful natural model for studying the effects of genetics and environment on the brain.Studies based on MRI have found that the asymmetry of human brain structure has a genetic basis.From the perspective of quantitative genetic analysis,this article reviews recent findings on the genetic effects of asymmetry and genetic covariance between hemispheres from three aspects:the asymmetry of heritability,the heritability of asymmetry and the genetic correlation.At last,the article shows the limitations and future research directions in this field.The purpose of this systematic review is to quickly guide researchers to understand the origins and genetic mechanism of interhemispheric differences,and provide a genetic basis for further understanding and exploring individual differences in laterized cognitive behavior.