Belief and Disbelief in the Existence of Genetic Risk Factors for Suicide: Cross-Cultural Comparisons

There is evidence for widespread disbelief in the genetics of suicide, despite recent research progress in this area and convergent evidence supporting a role for genetic factors. This study analyzed the beliefs held in 8 samples (total N=1224) of various types (psychology, medical, and various undergraduates, psychology graduates, and the general population) from 6 countries located on 3 continents (Austria, Canada, Malaysia, Romania, United Kingdom, and the USA). Endorsement rates for the existence of genetic risk factors for suicide ranged from 26% and 30% (Austrian psychology undergraduates and general population) to around 50% (psychology undergraduates in the USA and United Kingdom). In the 8 samples, respondents' sex, age, religiosity, political orientation, and other demographic variables were, for the most part, unrelated, but overall knowledge about suicide throughout was related positively to endorsement rates. Consistent with previous research, across a considerable variety of sample types and cultural settings there was no evidence for a clear majority believing in genetic bases for suicide.

The Cultural Meaning of Suicide: What Does That Mean?

Scholars sometimes stress that it is important to know the individual meaning of suicide and the cultural meaning of suicide, but the meaning of these terms remains unclear. The present article discusses this problem and suggests that the individual meaning of suicide is best based on the motives for suicide, while the cultural meaning of suicide is best rooted in the lay theories of suicide in which the members of cultures and subcultures believe.

Consistency of immigrant suicide rates in Austria with country-of-birth suicide rates: a role for genetic risk factors for suicide?

Multifaceted evidence (family, twin, adoption, molecular genetic, geographic, and surname studies of suicide) suggests genetic risk factors for suicide. The migrant study design is also informative in this context, but underused. In particular, immigrant studies of suicide with a continental European host country are unavailable. The correspondence of suicide prevalence among 22 immigrant groups in Austria (1970-2006) with those of the homelands during the same period was analyzed. Immigrant and homeland suicide rates were significantly positively associated. Controls for age of suicide victim, immigrant group size, national pride, and quality of life in the homelands left the finding essentially unchanged. This correspondence of immigrant and country-of-birth suicide rates is consistent with the assumption of population differences in the prevalence of genetic risk factors for suicide, for which there is emerging evidence.

Consistency of immigrant and country-of-birth suicide rates: a meta-analysis

OBJECTIVE

Multifaceted evidence (family, twin, adoption, molecular genetic, geographic and surname studies of suicide) suggests genetic risk factors for suicide. Migrant studies are also informative in this context, but underused. In particular, a meta-analysis of the associations of immigrant (IMM) and country-of-birth (COB) suicide rates is unavailable.

METHOD

Thirty-three studies, reporting IMM suicide rates for nearly 50 nationalities in seven host countries (Australia, Austria, Canada, England, the Netherlands, Sweden and the USA), were retrieved.

RESULTS

Total-population IMM and COB suicide rates were strongly positively associated (combined rank-order correlation across 20 eligible studies: 0.65, 95% CI: 0.56-0.73, P < 10(-9)). The effect generalized across both sexes, host countries and study periods.

CONCLUSION

Following the logic of the migrant study design of genetic epidemiology, the correspondence of IMM and COB suicide rates is consistent with the assumption of population differences in the prevalence of genetic risk factors for suicide.

A further test of the Finno-Ugrian Suicide Hypothesis: correspondence of county suicide rates in Romania and population proportion of ethnic Hungarians

Across the 42 counties of Romania, the total suicide rate and the population percentage of ethnic Hungarians were strongly positively interrelated (79% attributable variance). Counties with the strongest Hungarian minority had suicide rates converging to (or exceeding) the suicide rate for Hungary, which rate is high. Of a set of about 20 vital statistics and socioeconomic indicators, only life expectancy predicted a significant increment of further variance in the suicide rates. However, this effect was small, adding merely 3% further variance explained to 79% already accounted for. Overall, the findings are supportive of the Finno-Ugrian Suicide Hypothesis, i.e., the notion that geographic patterns of suicide prevalence may be partially due to genetic differences between populations. Supplemental analyses of a questionnaire item which specifically queried this study's main finding indicated widespread disbelief of this fact of suicide prevalence across a variety of samples, including two samples from Romania.