BDNF gene variants and brain morphology in schizophrenia

Abstract

The objective was to investigate putative associations between brain-derived neurotrophic factor gene (BDNF) polymorphisms and brain morphology in patients with schizophrenia and healthy control subjects. Four BDNF polymorphisms were genotyped and analyzed versus 39 brain volume measures in 96 patients with schizophrenia or schizoaffective disorder and 104 healthy subjects. In all subjects, quantitative data on segmented gray, white, and cerebrospinal fluid (CSF) tissue class volumes of total brain and major cerebral lobes including ventricular CSF were obtained using magnetic resonance imaging (MRI). In a randomly selected subset of this population (n = 101-122), MR volumes from cerebellar tonsil, hemispheres, and vermis subregions, striatal structures, hippocampus, and corpus callosum were also measured. The BDNF 11757 G/C polymorphism was highly significantly associated with frontal gray matter volume variation in patients alone and in patients and control subjects combined. In patients only, the 270 C/T polymorphism was associated with total caudate volume. Significant associations were demonstrated between the BDNF 11757 G/C and Val66Met polymorphisms and a global haplotype estimate of four BDNF polymorphisms and the posterior superior cerebellar vermis volume in the controls as well as in the combined group, but not in the patients. The 11757 G/C polymorphism was associated with cerebellar hemisphere white and gray matter volumes in the combined group. The BDNF -633 T/A polymorphism was associated with gray matter of the putamen in the controls. Trends for associations between several polymorphisms/haplotype estimates and MRI volumes were found. BDNF gene variation may influence brain morphology. The effects may be different in patients with schizophrenia and healthy subjects.