Background: Exposure to a traumatic event is required for the diagnosis of posttraumatic stress disorder (PTSM). The relation between psychopathological events, the phenomenology of the trauma, and ...neurobiological changes related to PTSM is not totally understood. The symptoms of PTSM are believed to reflect stress-induced changes in neurobiological systems representing an inadequate adaptation of neurobiological systems to exposure to severe stressors. Attempts are made to relate different neurobiological changes to the specific features represented in PTSM. It is not clear whether certain neurobiological changes in PTSM reflect preexisting vulnerability or consequences of trauma exposure. It is known that early life environmental events have persistent effects on central nervous tissue structure and function, a phenomenon called ‘developmental programming’. Further, it is known that glucocorticoid hormone mediators may be involved in this process. Recently, epigenetic differences in a neuron-specific glucocorticoid receptor promoter between suicide victims with a history of childhood abuse and those from suicide victims with no childhood abuse were found. It was suggested that changes in glucocorticoid system are mediated by tissue-specific changes in gene expression. Recent studies suggest that epigenetic mechanisms may play an important role in the interplay between stress exposure and genetic vulnerability. Conclusions: Integrating epigenetics into a model that permits prior experience to have a central role in determining individual differences is also consistent with a developmental perspective of PTSD vulnerability.
Introduction. Suicide is a multidimensional problem. Observations of family history of suicide suggest the existence of a genetic vulnerability to suicidal behaviour.
Aim. Starting with a historical ...perspective, the article reviews current knowledge of a genetic vulnerability to suicidal behaviour, distinct from the genetic vulnerability to psychiatric disorders, focused on clinical and population-based studies, and findings from recent molecular genetics association studies.
Method. The review includes peer-reviewed research articles and review papers from the professional literature in English language, retrieved from PubMed/Medline and PsycINFO.
Results. The research literature confirms a existence of a genetic vulnerability to suicidal behaviour. Even though the results of individual studies are difficult to compare, genetic influences could explain up to half of the variance of the occurrence of suicide.
Conclusion. Genetic vulnerability could be a distal risk factor for suicide, which helps us to understand the occurrence of suicide among vulnerable people. Ethical implications of such vulnerability are highlighted.
Uvod. Samomor je večrazsežnostni problem. S študijami družinskih anamnez samomorilnega vedenja je bilo ugotovljeno, da bi genetska komponenta lahko vplivala na občutljivost za samomorilno vedenje.
Namen. Članek skozi zgodovinski vidik proučuje današnje poznavanje genetske ranljivosti za samomorilno vedenje, ki se razlikuje od genetske ranljivosti za psihiatrične motnje v kliničnih in populacijskih študijah ter prikazuje ugotovitve zadnjih študij molekularno genetskih raziskav.
Metoda. Strokovni pregled vključuje raziskovalne članke in poročila iz strokovne literature v angleškem jeziku, pridobljene iz PubMed/Medine in PsycINFO.
Rezultati. Pregled obstoječe strokovne literature kaže na prisotnost genetske komponente kot dejavnika tveganja za samomorilno vedenje. Čeprav je rezultate posameznih študij težko primerjati, pa lahko genetski vplivi pojasnijo tudi do polovico različnih pojavov samomorilnega vedenja.
Zaključek. Genetska ranljivost bi lahko bila distalni dejavnik tveganja za samomor, kar nam pomaga razumeti pojav samomora med osebami s tveganjem za samomorilno vedenje. S tega pogleda so zajeta tudi etična vprašanja.
Psychiatric disorders, including suicide, are complex disorders that are affected by many different risk factors. It has been estimated that genetic factors contribute up to 50% to suicide risk. As ...the candidate gene approach has not identified a gene or set of genes that can be defined as biomarkers for suicidal behaviour, much is expected from cutting edge technological approaches that can interrogate several hundred, or even millions, of biomarkers at a time. These include the ‘-omic’ approaches, such as genomics, transcriptomics, epigenomics, proteomics and metabolomics. Indeed, these have revealed new candidate biomarkers associated with suicidal behaviour. The most interesting of these have been implicated in inflammation and immune responses, which have been revealed through different study approaches, from genome-wide single nucleotide studies and the micro-RNA transcriptome, to the proteome and metabolome. However, the massive amounts of data that are generated by the ‘-omic’ technologies demand the use of powerful computational analysis, and also specifically trained personnel. In this regard, machine learning approaches are beginning to pave the way towards personalized psychiatry.
In psychiatry, compared to other medical fields, the identification of biological markers that would complement current clinical interview, and enable more objective and faster clinical diagnosis, ...implement accurate monitoring of treatment response and remission, is grave. Current technological development enables analyses of various biological marks in high throughput scale at reasonable costs, and therefore 'omic' studies are entering the psychiatry research. However, big data demands a whole new plethora of skills in data processing, before clinically useful information can be extracted. So far the classical approach to data analysis did not really contribute to identification of biomarkers in psychiatry, but the extensive amounts of data might get to a higher level, if artificial intelligence in the shape of machine learning algorithms would be applied. Not many studies on machine learning in psychiatry have been published, but we can already see from that handful of studies that the potential to build a screening portfolio of biomarkers for different psychopathologies, including suicide, exists.
Objectives
This study evaluated the possible effects of ultrasound (US) on gene expression in brain tissue of rat embryos.
Methods
Four groups (n = 5 each) of pregnant Wistar Han rats were exposed to ...US for different durations (55, 100, 145, and 195 seconds) via a multifrequency transducer in the 2‐dimensional imaging mode with a pulse duration of 1.29 microseconds, a pulse repetition frequency of 1 kHz, and a derated spatial‐peak pulse‐average intensity of 222.4 W/cm2 on day 5, 9, 7, or 13 of gestation. Gene expression profiling was performed in fetal brain tissue (n = 5 per group) by quantitative reverse transcription–polymerase chain reaction arrays.
Results
The results indicated substantial alterations in gene expression. The most differentially expressed genes were Adamts5, Gadd45a, Npy2r, and Chrna1, which are implicated in important developmental signaling pathways.
Conclusions
On the basis of our findings, routine short US examinations for monitoring fetal development are not contraindicated, but prolonged exposures should be used only when needed to obtain important diagnostic information.
Suicide is a multidimensional problem. Observations of family history of suicide suggest the existence of a genetic vulnerability to suicidal behaviour.
Starting with a historical perspective, the ...article reviews current knowledge of a genetic vulnerability to suicidal behaviour, distinct from the genetic vulnerability to psychiatric disorders, focused on clinical and population-based studies, and findings from recent molecular genetics association studies.
The review includes peer-reviewed research articles and review papers from the professional literature in English language, retrieved from PubMed/Medline and PsycINFO.
The research literature confirms a existence of a genetic vulnerability to suicidal behaviour. Even though the results of individual studies are difficult to compare, genetic influences could explain up to half of the variance of the occurrence of suicide.
Genetic vulnerability could be a distal risk factor for suicide, which helps us to understand the occurrence of suicide among vulnerable people. Ethical implications of such vulnerability are highlighted.
Background: Exposure to a traumatic event is required for the diagnosis of posttraumatic stress disorder (PTSM). The relation between psychopathological events, the phenomenology of the trauma, and ...neurobiological changes related to PTSM is not totally understood. The symptoms of PTSM are believed to reflect stress-induced changes in neurobiological systems representing an inadequate adaptation of neurobiological systems to exposure to severe stressors. Attempts are made to relate different neurobiological changes to the specific features represented in PTSM. It is not clear whether certain neurobiological changes in PTSM reflect preexisting vulnerability or consequences of trauma exposure. It is known that early life environmental events have persistent effects on central nervous tissue structure and function, a phenomenon called 'developmental programming'. Further, it is known that glucocorticoid hormone mediators may be involved in this process. Recently, epigenetic differences in a neuron-specific glucocorticoid receptor promoter between suicide victims with a history of childhood abuse and those from suicide victims with no childhood abuse were found. It was suggested that changes in glucocorticoid system are mediated by tissue-specific changes in gene expression. Recent studies suggest that epigenetic mechanisms may play an important role in the interplay between stress exposure and genetic vulnerability. Conclusions: Integrating epigenetics into a model that permits prior experience to have a central role in determining individual differences is also consistent with a developmental perspective of PTSD vulnerability.
Background: Serotonin (5-HT) is an important neurotransmitter with wide-ranging functions. Its disfunction in the central
nervous system seems to play an important role in many psychiatric disorders ...and suicidal behavior. The objective of this study was
to examine the association between polymorphisms in different serotonin receptor genes (HTR): HTR1A (polymorphism -1019C>G),
HTR1B (polymorphisms 861G>C and -161A>T), HTR1F (polymorphism -78C>T) and HTR2A (polymorphism -1420C>T), and
serotonin transporter gene (5-HTT) (polymorphism LPR in promoter and VNTR in the second intron), and completed alcohol-related
suicide, as well as between alcohol-dependent suicide victims.
Subjects and methods: The study subjects were 373 Slovenian suicide victims (mean age ±SD: 48.8±17.7 years) autopsied in the
years 2002 through 2005. During autopsy venous blood was drawn, and afterwards DNA extraction and alcoholimetric analysis
were performed. Relatives of 79 suicide victims were interviewed using a semi-structured questionnaire designed according to
Slovenian cultural and economic conditions. They provided information about the alcohol abuse of the suicide victims. Amongst the
suicide victims were 25 alcohol misusers and 54 non-misusers.
Results: Association between polymorphisms in the selected serotonin receptor genes, transporter gene and completed alcoholrelated
suicide, as well as between alcohol-dependent suicide victims was not established.
Conclusions: Present results suggest that selected polymorphisms of the 5-HT receptor genes and transporter gene are not
involved in genetic susceptibility to completed suicide under acute influence of alcohol or among alcohol-dependent individuals, but
further studies in a larger sample are needed.
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