Influence of X chromosome and hormones on human brain development: a magnetic resonance imaging and proton magnetic resonance spectroscopy study of Turner syndrome.
BACKGROUND
Women with Turner syndrome (TS; 45,X) lack a normal second X chromosome, and many are prescribed exogenous sex and growth hormones (GH). Hence, they allow us an opportunity to investigate genetic and endocrine influences on brain development.


METHODS
We examined brain anatomy and metabolism in 27 adult monosomic TS women and 21 control subjects with volumetric magnetic resonance imaging and magnetic resonance spectroscopy.


RESULTS
In TS women, regional gray matter volume was significantly smaller in parieto-occipital cortex and caudate nucleus and larger in cerebellar hemispheres. White matter was reduced in the cerebellar hemispheres, parieto-occipital regions, and splenium of the corpus callosum but was increased in the temporal and orbitofrontal lobes and genui of corpus callosum. Women with TS had a significantly lower parietal lobe concentration of N-acetyl aspartate, and higher hippocampal choline. Also, among women with TS, there were significant differences in regional gray matter volumes and/or neuronal integrity, depending upon parental origin of X chromosome and oxandrolone and GH use.


CONCLUSIONS
X chromosome monosomy, imprinting and neuroendocrine milieu modulate human brain development-perhaps in a regionally specific manner.
Cutter
William J
WJ
Section of Brain Maturation, Department of Psychological Medicine, Institute of Psychiatry, De Crespigny Park, Denmark Hill, London SE5 8AF, UK. sppmwjc@iop.kcl.ac.uk
Daly
Eileen M
EM
Robertson
Dene M W
DM
Chitnis
Xavier A
XA
van Amelsvoort
Therese A M J
TA
Simmons
Andrew
A
Ng
Virginia W K
VW
Williams
Benjamin S
BS
Shaw
Phillip
P
Conway
Gerard S
GS
Skuse
David H
DH
Collier
David A
DA
Craig
Michael
M
Murphy
Declan G M
DG
D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000187:drug effects / Q000473:pathology*; D002794:Choline / Q000378:metabolism; D041321:Chromosomes, Human, X / Q000502:physiology*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000627:therapeutic use*; D019382:Human Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D009006:Monosomy / Q000235:genetics; D010074:Oxandrolone / Q000627:therapeutic use; D014424:Turner Syndrome / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology*
D012739:Gonadal Steroid Hormones; D019382:Human Growth Hormone; D001224:Aspartic Acid; D010074:Oxandrolone; C000179:N-acetylaspartate; D002794:Choline