TY - JOUR
T1 - Intrapair differences in hippocampal volume in monozygotic twins discordant for the risk for anxiety and depression.
AU - de Geus, E.J.C.
AU - van t Ent, D.
AU - Wolfensberger, S.P.A.
AU - Heutink, P.
AU - Hoogendijk, W.J.G.
AU - Boomsma, D.I.
AU - Veltman, D.J.
PY - 2007
Y1 - 2007
N2 - Background: Current biological psychiatric models assume that genetic and environmental risk factors for anxiety and depression act on the same brain structures. Methods: To test this assumption, we assessed brain anatomy by using optimized voxel-based morphometry on magnetic resonance images obtained in monozygotic twin pairs who were discordant for the risk of anxiety and depression (n = 10 pairs) and in monozygotic twin pairs who were concordant for high (n = 7 pairs) or low (n = 15 pairs) risk for anxiety and depression. Results: We observed volume reductions in the temporal lobe, most notably in the left posterior hippocampal region in subjects at high risk for anxiety and depression, but exclusively in the intrapair comparison of discordant monozygotic twins. Because monozygotic twins are genetically identical, any discordance in their risk for anxiety and depression and hippocampal volume must arise from differential exposure to environmental influences. A group comparison between pairs concordant for low or high risk, which is more likely to reflect differences in genetic vulnerability, did not show reduced temporal-lobe and posterior hippocampal volumes in the pairs at high risk for anxiety and depression. Conclusions: This pattern of results suggests that damage to temporal-lobe structures may be specific to an environmentally driven etiology of anxiety and depression. © 2007 Society of Biological Psychiatry.
AB - Background: Current biological psychiatric models assume that genetic and environmental risk factors for anxiety and depression act on the same brain structures. Methods: To test this assumption, we assessed brain anatomy by using optimized voxel-based morphometry on magnetic resonance images obtained in monozygotic twin pairs who were discordant for the risk of anxiety and depression (n = 10 pairs) and in monozygotic twin pairs who were concordant for high (n = 7 pairs) or low (n = 15 pairs) risk for anxiety and depression. Results: We observed volume reductions in the temporal lobe, most notably in the left posterior hippocampal region in subjects at high risk for anxiety and depression, but exclusively in the intrapair comparison of discordant monozygotic twins. Because monozygotic twins are genetically identical, any discordance in their risk for anxiety and depression and hippocampal volume must arise from differential exposure to environmental influences. A group comparison between pairs concordant for low or high risk, which is more likely to reflect differences in genetic vulnerability, did not show reduced temporal-lobe and posterior hippocampal volumes in the pairs at high risk for anxiety and depression. Conclusions: This pattern of results suggests that damage to temporal-lobe structures may be specific to an environmentally driven etiology of anxiety and depression. © 2007 Society of Biological Psychiatry.
U2 - 10.1016/j.biopsych.2006.07.026
DO - 10.1016/j.biopsych.2006.07.026
M3 - Article
SN - 0006-3223
VL - 61
SP - 1062
EP - 1071
JO - Biological Psychiatry
JF - Biological Psychiatry
IS - 9
ER -