Background
Our previous genome-wide association study (CONVERGE sample)
identified significant association between single nucleotide polymorphisms (SNPs) near the SIRT1 gene and major depressive
disorder (MDD) in Chinese populations.
Aims
To investigate whether SNPs across the SIRT1 gene locus affect
regional grey matter density in the Han Chinese population.
Method
T1-weighted structural magnetic resonance imaging was conducted
on 92 healthy participants from Eastern China. Grey
matter was segmented from the image, which consisted of
voxel-wise grey matter density. The effect of SIRT1 SNPs on grey
matter density was determined by a multiple linear regression
framework.
Results
SNP rs4746720 was significantly associated with grey matter
density in two brain cortical regions: the orbital part of the right
inferior frontal gyrus and the orbital part of the left inferior
frontal gyrus (family-wise error-corrected P < 0.05; voxel-wise
P < 0.001). Also, rs4746720 exceeded genome-wide significance
in association with MDD in our CONVERGE sample (P = 3.32 × 10−08, odds ratio 1.161).
Conclusions
Our results provided evidence for a potential role of the SIRT1
gene in the brain, implying a possible pathophysiological
mechanism underlying susceptibility to MDD.