Distinct Genetic Influences on Cortical and Subcortical Brain Structures.
This study examined the heritability of brain grey matter structures in a subsample of older adult twins (93 MZ and 68 DZ twin pairs; mean age 70 years) from the Older Australian Twins Study. The heritability estimates of subcortical regions ranged from 0.41 (amygdala) to 0.73 (hippocampus), and of cortical regions, from 0.55 (parietal lobe) to 0.78 (frontal lobe). Corresponding structures in the two hemispheres were influenced by the same genetic factors and high genetic correlations were observed between the two hemispheric regions. There were three genetically correlated clusters, comprising (i) the cortical lobes (frontal, temporal, parietal and occipital lobes); (ii) the basal ganglia (caudate, putamen and pallidum) with weak genetic correlations with cortical lobes, and (iii) the amygdala, hippocampus, thalamus and nucleus accumbens grouped together, which genetically correlated with both basal ganglia and cortical lobes, albeit relatively weakly. Our study demonstrates a complex but patterned and clustered genetic architecture of the human brain, with divergent genetic determinants of cortical and subcortical structures, in particular the basal ganglia.
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.|Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, NSW 2031, Australia.
Wei
W
Wen
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.
Anbupalam
A
Thalamuthu
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.
Karen A
KA
Mather
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.|Department of Mathematics and Statistics, University of Montreal, Montreal, QC H3T1J4, Canada.
Wanlin
W
Zhu
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.
Jiyang
J
Jiang
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.|Department of Mathematics and Statistics, University of Montreal, Montreal, QC H3T1J4, Canada.|School of Mathematics and Statistics, University of New South Wales, Sydney, NSW 2052, Australia.
Pierre Lafaye
PL
de Micheaux
Queensland Brain Institute, University of Queensland, St Lucia, QLD 4072, Australia.|Centre for Advanced Imaging, University of Queensland, St Lucia, QLD 4072, Australia.
Margaret J
MJ
Wright
National Aging Research Institute, University of Melbourne, Parkville, VIC 3052, Australia.
David
D
Ames
Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW 2052, Australia.|Neuropsychiatric Institute, Prince of Wales Hospital, Randwick, NSW 2031, Australia.
Perminder S
PS
Sachdev
D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008297:Male; D008953:Models, Anatomic; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*