PS46. Distinct and shared morphometric biomarkers of depressed individuals with bipolar disorder and major depressive disorder
International Journal of Neuropsychopharmacology
Previous studies have suggested an association between CACNA1C and susceptibility of bipolar disorder. In this study, we examined the association of CACNA1C variants with bipolar disorder in the Korean population. We selected 2 CACNA1C single nucleotide polymorphisms (SNPs), namely, rs723672 and rs1051375, based on their functions and minor allele frequencies described in previous studies. After purifying DNA from blood samples collected from 340 healthy controls and 287 patients with bipolar
... ents with bipolar disorder, the genotypes of 2 CACNA1C SNPs were analyzed. Genotype frequencies of both rs723672 and rs1051375 SNPs were significantly different in patients and controls (p = 0.0462 and 1.732 × 10 -14 , respectively). Dominant, recessive, and allele models showed significant differences between patients and controls with respect to the rs1051375 SNP (p = 1.72 × 10 -11 , 4.17 × 10 -10 , and 4.95 × 10 -16 , respectively). Our results suggested that CACNA1C SNPs rs723672 and rs1051375 were associated with bipolar disorder in the Korean population. In addition, our results highlighted the importance of CACNA1C in determining susceptibility to bipolar disorder. Abstract Objective: Diagnostic differentiation between depressed patients with bipolar disorder or major depressive disorder is a critical issue, as misdiagnosis may result in inappropriate treatment and poor outcome. Specific biomarkers of each disorder that would allow differential diagnosis have not been identified. The aim of study is to determine whether depressed patients with bipolar disorder or major depressive disorder show distinct morphometric abnormalities. Methods: 569 depressed patients with major depressive disorder, 140 depressed patients with bipolar disorder, and 717 age-matched healthy participants were studied. We examined gray matter volume using voxel-based morphometry. Group classification was performed using a support vector machine algorithm. Abstract Normal subjects with bipolarity phenotype, even though not diagnosed bipolar disorder, are known to show distinct properties. In this study, we investigate the changes in molecular circadian rhythm after bright light exposure before sleep in normal subjects with bipolarity phenotype. 25 young male subjects were divided to 14 for bipolarity group and 11 for nonbipolarity group after scoring of the mood disorder questionnaire (MDQ). During the first two study days, the subjects were exposed to the normal-living light (150 lux) for 2.5 hours before sleep, and the saliva and buccal cells of subjects were collected for a total six regular times periodically. During the subsequent five days, the subjects were exposed to the bright light (1,000 lux), and the saliva and buccal cells were collected in the same way. The molecular circadian rhythm of cortisol and circadian gene expression ratio (Per1/Bmal1) were analyzed with cosinor regression. Circadian rhythm of cortisol showed a delay of acrophase in both groups after bright light exposure (p<0.001), and bipolarity group showed a significant delay than non-bipolar group (p=0.008). Circadian rhythm of circadian gene expression ratio showed a delay of acrophase (p<0.001) and a decrease of amplitude (p<0.001) after bright light exposure in both groups, but there was no group difference. Bipolarity group showed hypersensitivity in cortisol rhythm than non-bipolarity group after bright light exposure, but not in circadian gene expression. These results suggest that the characteristic molecular circadian rhythm change of bipolarity group may be related to the biological process after circadian gene expression.