TY - JOUR
T1 - Familial and environmental influences on brain volumes in twins with schizophrenia
AU - Picchioni, Marco M
AU - Rijsdijk, Fruhling
AU - Toulopoulou, Timothea
AU - Chaddock, Christopher
AU - Cole, James H
AU - Ettinger, Ulrich
AU - Oses, Ana
AU - Metcalfe, Hugo
AU - Murray, Robin M
AU - McGuire, Philip
PY - 2017/3
Y1 - 2017/3
N2 - Background: Reductions in whole brain and grey matter volumes are robust features of schizophrenia, yet their etiological influences are unclear. Methods: We investigated the association between the genetic and environmental risk for schizophrenia and brain volumes. Whole brain, grey matter and white matter volumes were established from structural MRIs from twins varying in their zygosity and concordance for schizophrenia. Hippocampal volumes were measured manually. We conducted between-group testing and full genetic modelling. Results: We included 168 twins in our study. Whole brain, grey matter, white matter and right hippocampal volumes were smaller in twins with schizophrenia. Twin correlations were larger for whole brain, grey matter and white matter volumes in monozygotic than dizygotic twins and were significantly heritable, whereas hippocampal volume was the most environmentally sensitive. There was a significant phenotypic correlation between schizophrenia and reductions in all the brain volumes except for that of the left hippocampus. For whole brain, grey matter and the right hippocampus the etiological links with schizophrenia were principally associated with the shared familial environment. Lower birth weight and perinatal hypoxia were both associated with lower whole brain volume and with lower white matter and grey matter volumes, respectively. Limitations: Scan data were collected across 2 sites, and some groups were modest in size. Conclusion: Whole brain, grey matter and right hippocampal volume reductions are linked to schizophrenia through correlated familial risk (i.e., the shared familial environment). The degree of influence of etiological factors varies between brain structures, leading to the possibility of a neuroanatomically specific etiological imprint.
AB - Background: Reductions in whole brain and grey matter volumes are robust features of schizophrenia, yet their etiological influences are unclear. Methods: We investigated the association between the genetic and environmental risk for schizophrenia and brain volumes. Whole brain, grey matter and white matter volumes were established from structural MRIs from twins varying in their zygosity and concordance for schizophrenia. Hippocampal volumes were measured manually. We conducted between-group testing and full genetic modelling. Results: We included 168 twins in our study. Whole brain, grey matter, white matter and right hippocampal volumes were smaller in twins with schizophrenia. Twin correlations were larger for whole brain, grey matter and white matter volumes in monozygotic than dizygotic twins and were significantly heritable, whereas hippocampal volume was the most environmentally sensitive. There was a significant phenotypic correlation between schizophrenia and reductions in all the brain volumes except for that of the left hippocampus. For whole brain, grey matter and the right hippocampus the etiological links with schizophrenia were principally associated with the shared familial environment. Lower birth weight and perinatal hypoxia were both associated with lower whole brain volume and with lower white matter and grey matter volumes, respectively. Limitations: Scan data were collected across 2 sites, and some groups were modest in size. Conclusion: Whole brain, grey matter and right hippocampal volume reductions are linked to schizophrenia through correlated familial risk (i.e., the shared familial environment). The degree of influence of etiological factors varies between brain structures, leading to the possibility of a neuroanatomically specific etiological imprint.
UR - http://www.scopus.com/inward/record.url?scp=85013970791&partnerID=8YFLogxK
U2 - 10.1503/jpn.140277
DO - 10.1503/jpn.140277
M3 - Article
C2 - 28245176
SN - 1180-4882
VL - 42
SP - 122
EP - 130
JO - Journal of psychiatry & neuroscience : JPN
JF - Journal of psychiatry & neuroscience : JPN
IS - 2
ER -