The rs7208505 Polymorphism and Differential Expression of the SKA2 Gene in the Prefrontal Cortex of Suicide Victims from the Mexican Population.

OBJECTIVE: The main aim of the current study was to investigate whether SKA2 gene expression in the postmortem brain of rs7208505 genotype are altered in suicide victims from a Mexican population. METHODS: In this study, we report a genetic analysis of expression levels of the SKA2 gene in the prefrontal cortex of the postmortem brain of suicidal subjects (n = 22) compared to subjects who died of causes other than suicide (n = 22) in a Mexican population using RT-qPCR assays. Additionally, we genotyped the rs7208505 polymorphism in suicide victims (n = 98) and controls (n = 88) and we evaluate the association of genotypes for the SNP rs7208505 with expression level of SKA2. RESULTS: The results showed that the expression of the SKA2 gene was significantly higher in suicide victims compared to control subjects (p = 0.044). Interestingly, we observed a greater proportion of allele A of the rs7208505 in suicide victims than controls. Even though there was no association between the SNP with suicide in the study population we found a significative association of the expression level from SKA2 with the allele A of the rs7208505 and suicide. CONCLUSION: The evidence suggests that the expression of SKA2 in the prefrontal cortex may be a critical factor in the etiology of suicidal behavior.

HighlightsSuicide victims have a higher level of SKA2 gene expression in the brain's prefrontal cortex than control subjects.The SKA2 rs7208505 is not associated with suicide in the Mexican population studied.Allele frequencies for G are higher than allele frequencies for A in our study population.The allele A of the rs7208505 affects the expression values of the SKA2 gene.

Differential expression of HTR2A and MAOA genes in the prefrontal cortex and hypothalamus of suicide victims from Mexican population.

OBJECTIVE: The main aim of the current study was to investigate whether the expression levels of the HTR2A and MAOA genes are altered in the postmortem brain of suicide victims from Mexican population. METHODS: On the basis of a case- control study, we examined the expression levels of HTR2A and MAOA genes in the postmortem prefrontal cortex (Brodmann area 8/9) and hypothalamus (ventromedial nucleus) tissues from 20 suicide victims and 20 control subjects from a Mexican population. Gene-expression profile quantification was carried out by qPCR and determined by the 2-ΔΔCt method. RESULTS: In suicide victims, the expression levels of the HTR2A gene were significantly higher in the prefrontal cortex. In contrast, the expression of the MAOA gene in the hypothalamus of the suicide victims was significantly higher than in the control subjects. These results were consistent regardless of age, sex, postmortem interval, or pH of brain tissue. CONCLUSION: The evidence suggests that the pattern of differential expression of HTR2A and MAOA genes in the brain may be involved in suicide, providing a possible molecular basis for the brain abnormalities in suicide victims.

Epigenetic marks in suicide: a review.

Suicide is a complex phenomenon and a global public health problem that involves several biological factors that could contribute to the pathophysiology of suicide. There is evidence that epigenetic factors influence some psychiatric disorders, suggesting a predisposition to suicide or suicidal behavior. Here, we review studies of molecular mechanisms of suicide in an epigenetic perspective in the postmortem brain of suicide completers and peripheral blood cells of suicide attempters. Besides, we include studies of gene-specific DNA methylation, epigenome-wide association, histone modification, and interfering RNAs as epigenetic factors. This review provides an overview of the epigenetic mechanisms described in different biological systems related to suicide, contributing to an understanding of the genetic regulation in suicide. We conclude that epigenetic marks are potential biomarkers in suicide, and they could become attractive therapeutic targets due to their reversibility and importance in regulating gene expression.