Department of Psychology, Laboratory of Neurogenetics, University of Bonn, Germany.
Psychol Med. 2009 Nov;39(11):1831-9. doi: 10.1017/S0033291709005509. Epub 2009 Apr 1.
The role of the brain-derived neurotrophic factor (BDNF) in the pathogenesis of affective disorders such as depression has been controversial. Mounting evidence comes from structural imaging, that the functional BDNF Val66Met polymorphism influences the hippocampal volume with carriers of the 66Met allele (Val/Met and Met/Met group) having smaller hippocampi. Given that stress-induced atrophy of the hippocampus is associated with the pathogenesis of affective disorders, the functional BDNF Val66Met polymorphism could be an incremental risk factor.
Eighty-seven healthy Caucasian participants underwent structural imaging and were genotyped for the BDNF Val66Met polymorphism. Data were analysed by means of voxel-based morphometry (VBM).
Region of interest (ROI) analyses revealed an association between the 66Met allele and smaller parahippocampal volumes and a smaller right amygdala. In addition, the whole-brain analysis showed that the thalamus, fusiformus gyrus and several parts of the frontal gyrus were smaller in 66Met allele carriers.
This study demonstrates that the impact of the BDNF Val66Met polymorphism is not confined to the hippocampus but also extends to the parahippocampal gyrus and the amygdala.
脑源性神经营养因子（BDNF）在情感障碍（如抑郁症）发病机制中的作用一直存在争议。越来越多的证据来自结构影像学研究，即功能性 BDNF Val66Met 多态性影响海马体积，携带 66Met 等位基因（Val/Met 和 Met/Met 组）的个体海马体积较小。鉴于应激诱导的海马萎缩与情感障碍的发病机制有关，功能性 BDNF Val66Met 多态性可能是一个额外的风险因素。
87 名健康的白种人参与者接受了结构影像学检查，并对 BDNF Val66Met 多态性进行了基因分型。数据通过基于体素的形态测量学（VBM）进行分析。
感兴趣区域（ROI）分析显示，66Met 等位基因与较小的海马旁回体积和较小的右侧杏仁核有关。此外，全脑分析显示，66Met 等位基因携带者的丘脑、梭状回和额回的几个部分体积较小。
这项研究表明，BDNF Val66Met 多态性的影响不仅局限于海马体，还扩展到海马旁回和杏仁核。
