Mapping 22q11.2 Gene Dosage Effects on Brain Morphometry

Reciprocal chromosomal rearrangements at the 22q11.2 locus are associated with elevated risk of neurodevelopmental disorders. The 22q11.2 deletion confers the highest known genetic risk for schizophrenia, but a duplication in the same region is strongly associated with autism and is less common in s...

Full description

Saved in:

Bibliographic Details
Published in:	The Journal of neuroscience Vol. 37; no. 26; pp. 6183 - 6199
Main Authors:	Lin, Amy, Ching, Christopher R K, Vajdi, Ariana, Sun, Daqiang, Jonas, Rachel K, Jalbrzikowski, Maria, Kushan-Wells, Leila, Pacheco Hansen, Laura, Krikorian, Emma, Gutman, Boris, Dokoru, Deepika, Helleman, Gerhard, Thompson, Paul M, Bearden, Carrie E
Format:	Journal Article
Language:	English
Published:	United States Society for Neuroscience 28-06-2017
Subjects:	22q11 Deletion Syndrome - genetics 22q11 Deletion Syndrome - pathology Amygdala Autism Brain Brain - pathology Brain - physiopathology Brain Mapping Chromosome 22 Chromosome rearrangements Copy number Corpus callosum Cortex DNA Copy Number Variations - genetics Dosage Female Gene deletion Gene dosage Gene Dosage - genetics Gene mapping Gene Rearrangement - genetics Hippocampus Humans Male Males Mental disorders Middle Aged Morphometry Neurodevelopmental disorders Organ Size - genetics Phenotypes Putamen Reproduction (copying) Schizophrenia Substantia alba Surface area Thalamus copy number variant structural neuroimaging chromosome 22 neurodevelopment autism spectrum disorder psychosis
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Reciprocal chromosomal rearrangements at the 22q11.2 locus are associated with elevated risk of neurodevelopmental disorders. The 22q11.2 deletion confers the highest known genetic risk for schizophrenia, but a duplication in the same region is strongly associated with autism and is less common in schizophrenia cases than in the general population. Here we conducted the first study of 22q11.2 gene dosage effects on brain structure in a sample of 143 human subjects: 66 with 22q11.2 deletions (22q-del; 32 males), 21 with 22q11.2 duplications (22q-dup; 14 males), and 56 age- and sex-matched controls (31 males). 22q11.2 gene dosage varied positively with intracranial volume, gray and white matter volume, and cortical surface area (deletion < control < duplication). In contrast, gene dosage varied negatively with mean cortical thickness (deletion > control > duplication). Widespread differences were observed for cortical surface area with more localized effects on cortical thickness. These diametric patterns extended into subcortical regions: 22q-dup carriers had a significantly larger right hippocampus, on average, but lower right caudate and corpus callosum volume, relative to 22q-del carriers. Novel subcortical shape analysis revealed greater radial distance (thickness) of the right amygdala and left thalamus, and localized increases and decreases in subregions of the caudate, putamen, and hippocampus in 22q-dup relative to 22q-del carriers. This study provides the first evidence that 22q11.2 is a genomic region associated with gene-dose-dependent brain phenotypes. Pervasive effects on cortical surface area imply that this copy number variant affects brain structure early in the course of development. Probing naturally occurring reciprocal copy number variation in the genome may help us understand mechanisms underlying deviations from typical brain and cognitive development. The 22q11.2 genomic region is particularly susceptible to chromosomal rearrangements and contains many genes crucial for neuronal development and migration. Not surprisingly, reciprocal genomic imbalances at this locus confer some of the highest known genetic risks for developmental neuropsychiatric disorders. Here we provide the first evidence that brain morphology differs meaningfully as a function of reciprocal genomic variation at the 22q11.2 locus. Cortical thickness and surface area were affected in opposite directions with more widespread effects of gene dosage on cortical surface area.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 Author contributions: B.G., P.M.T., and C.E.B. designed research; A.L., C.R.K.C., A.V., D.S., R.K.J., M.J., L.K.-W., L.P.H., E.K., B.G., D.D., and C.E.B. performed research; C.R.K.C., B.G., and G.H. contributed unpublished reagents/analytic tools; A.L., C.R.K.C., D.S., and R.K.J. analyzed data; A.L., C.R.K.C., R.K.J., P.M.T., and C.E.B. wrote the paper.
ISSN:	0270-6474 1529-2401
DOI:	10.1523/JNEUROSCI.3759-16.2017