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Angela
22-12-17, 18:02
See:
https://www.biorxiv.org/content/biorxiv/early/2017/12/19/234674.full.pdf

I'm not at all surprised...

"Background: Heritability of suicide risk is estimated at 43%, thus genetic risk likely plays an importantrole in completion of suicide. Previous genetic research has focused primarily on suicidal behavior orideation rather than actual completed suicide. And previous genome-wide association studies ofcompletion of suicide have been very small due to the difficulty in obtaining suicide sample data, andhave been unable to identify genome-wide significant variants, likely due to power limitations. This studypresents results from the first wave of a large Utah sample of completed suicides, and represent themost statistically powerful sample of completed suicide to date.Methods: Tissue samples from 1321 decedents were collected via partnership with the Utah Office ofthe Medical Examiner and genotyped using the Illumina Infinium PsychArray platform. Bioconductorpackage RaMWAS (A.S.) was used on post-QC hard call data (271,894 common variants) to conductGWAS. Because the sample is from Utah, the authors were able to conduct a relatively directcomparison with 1000 Genomes controls also from Utah (CEU), as well as European controls (EUR). Thefirst GWAS with Utah CEU controls (n of only 99) was followed by a second GWAS with EUR controls (n= 503) with and without CEU included in the control sample.Results: Analyses identified 8 SNPs in 6 genes associated with the completion of suicide. Six SNPs metgenome-wide significance. Two of these variant hits were replicated using EUR controls not includingthe CEU sample, though the case sample was the same in both analyses. Subsequent QC steps (linkagedisequilibrium analysis and EUR GWAS replication) further substantiated significant results implicatingcytochrome P450 genes.Conclusions: This GWAS and partial replication of findings across control samples, using hard callgenotype data, represents a significant step toward understanding the genetic architecture of suicide.These are late-breaking results, and in January this group will follow up with analyses using the full 2waves (N = 4800 cases), a larger control group, and imputed data to ~11 million variants. Analyses todate implicate cytochrome P450 sites involved in metabolism of arachidonic acid and relatedinflammatory mediators. Results implicate inflammation in suicide risk, and add to a growing body ofevidence that lung function may be tied to suicide."

Jovialis
22-12-17, 18:25
https://i.imgur.com/d0GoNDb.png
http://www.who.int/mental_health/prevention/suicide/suicideprevent/en/
https://en.wikipedia.org/wiki/List_of_sovereign_states_by_suicide_rate

-The highest rate of suicide seems to be in Sri Lanka
-Followed by Guyana, which has a large Indian population. The map indicates that India also has a large suicide rate.
-Mongolia coming in third.

There's no doubt that genetics plays a role in suicide; as to why it is higher in some first-world countries (i.e. Japan). But I wonder if some of the other cases may be caused by living-conditions, like in third world countries. Or rather, living-conditions, combined with genetic predisposition would drive someone to this.

Angela
22-12-17, 18:32
Other than genetic factors, I don't know what would cause the differences in Europe. Perhaps it's tied to alcohol abuse? On the other hand, the latter is tied to depression, which also has a strong genetic component.

https://jakubmarian.com/wp-content/uploads/2016/09/suicides-europe.jpg

davef
22-12-17, 18:41
Heritability of suicide? I don't see the point to this study. You don't inherit suicide, you inherit the depression which puts you at risk for suicidal tendencies.

Angela
22-12-17, 19:29
I think suicide is a bit different. Yes, it must stem from depression, but while a lot of people suffer from clinical depression, most never progress to suicide.

I think some of it has nothing to do with genetics necessarily. Certain life situations are so terrible that it can drive people to it.

davef
22-12-17, 20:02
I think suicide is a bit different. Yes, it must stem from depression, but while a lot of people suffer from clinical depression, most never progress to suicide.

I think some of it has nothing to do with genetics necessarily. Certain life situations are so terrible that it can drive people to it.
true, but i meant suicide risk, sorry. The idea of a "suicide gene" sounds pretty unreasonable from my view, as nobody healthy enough would just choose to off themselves out of the blue; I would expect someone in good health to maintain a desire to live. If suicide is driven by genes, it would have to come from clinical depression which I would guess is inherited.

michaelpkingston
02-01-18, 16:18
following this thread