(HealthDay News) – Genetic variants associated with brain size have been identified, including one variant which correlates with hippocampal volume, where size has been associated with Alzheimer’s disease and other neurological disorders.
Jason L. Stein, from the University of California in Los Angeles, and colleagues used data from a large multinational consortium and conducted a genome-wide association meta-analysis and replication study for bilateral hippocampal, total brain, and intracranial volumes.
The researchers found that one variant (rs7294919) was significantly associated with hippocampal volume, which was associated with expression of the positional candidate gene TESC in the brain. This variant was associated with a 47.6mm3 reduction in hippocampal volume per allele. Another variant located within HMGA2 (rs10784502) correlated with intracranial volume and was associated with increased intracranial volume and increased full-scale IQ. A suggestive association was identified for a third variant within DDR2 (rs10494373), which correlated with total brain volume.
“The current study identified and replicated two quantitative trait loci for hippocampal and intracranial volumes across lifespan in a large sample, including both healthy subjects and those with neuropsychiatric diagnoses,” Stein and colleagues conclude. “It remains to be determined whether specific genetic variations linked to volumetric brain differences are also associated with other neuropsychiatric disorders, brain function and other cognitive traits.”
Several authors disclosed financial relationships with the biotechnology, pharmaceutical, and medical device industries.