Genetic risk factors and variation in European suicide rates

D. Lester

The Richard Stockton College of New Jersey, PO Box 195, Jim Leeds Road, Pomona, NJ 08240-0195, USA

S. V. Kondrichin

Minsk Regional Hospital, Minsk, Belarus

Marui & Farmer (2001) argued that genetic factors may play a role in the variation of suicide rates in European nations. They suggested the role of the Finno-Ugrian ethnic group and the possibility that genetic factors play a role in the alcohol—suicide link. We have conducted two studies that support their argument.

First, we quantified the influence of Finno-Ugrians on European suicide rates by correlating the suicide rate of all 30 European nations with the percentage of Finno-Ugrians in the population (Kondrichin & Lester, 1997). The Pearson correlation coefficient was 0.58 (two-tailed P < 0.01).

Second, Lester (1987) calculated the proportion of people with type O blood in 17 industrialised nations (including 12 Western European nations) and correlated this with the suicide rates. The Pearson correlation was -0.67 (two-tailed P < 0.01). Lester then noted that people in Hungary and Czechoslovakia (both in the Eastern European bloc at the time and not in the original sample) had very low proportions of type O blood and very high suicide rates compared with the original sample.

These two studies support the suggestion of Marui & Farmer that genetic factors may play a role in the variation in European suicide rates.

EDITED BY MATTHEW HOTOPF

REFERENCES

Kondrichin, S. V. & Lester, D. (1997) Finno-Ugrians and suicide. Perceptual & Motor Skills, 85, 514.

Lester, D. (1987) National distribution of blood groups, personal violence (suicide and homicide), and national character. Personality & Individual Differences, 8, 575-576.[CrossRef]

Marui, A. & Farmer, A. (2001) Genetic risk factors as possible causes of the variation in European suicide rates. British Journal of Psychiatry, 179, 194-196.[Free Full Text]


 

Authors' reply

A. Marui and A. Farmer

Social, Genetic & Developmental Psychiatry Research Centre, Institute of Psychiatry, De Crespigny Park, Denmark Hill, London SE5 8AF, UK

EDITED BY MATTHEW HOTOPF

We are grateful to Lester & Kondrichin for pointing out the high correlations between the suicide rates in 30 countries with the percentage of Finno-Ugrians in the population, and of the negative correlations of suicide rates with the proportions of people with blood type O in different countries. This certainly provides additional evidence in support of our hypothesis.

Tunstall is more critical and his important comments require a considered response. He states that we have not addressed the issue of other sociocultural factors that may be relevant to the differences in European suicide rates. It has been pointed out elsewhere (e.g. Diekstra, 1993) that rate variation due to some such factors evens out when considered across countries, and can probably be ignored. Also, as we have pointed out, sociocultural explanations alone cannot explain the rate found in our ‘black swan’ example, Slovenia.

For brevity in a short editorial, we did not explore the ‘potential confounder’ of the prevalence of psychiatric disorder in different countries in our paper, although contrary to Tunstall's assertion, we have not neglected to discuss the complex relationship between alcohol consumption and suicide. Not only do we consider in some detail the possible malignant interaction between alcohol exposure and genetic constitution in Slovenia, but we also point out the complex association between alcohol consumption and suicide rates elsewhere in Europe, citing Sweden and France as examples.

Tunstall suggests that Finland is a more ‘anxious culture’ than Sweden. While this may be true, we none the less contend that such cultural anxiety would also have genetic underpinnings. Measures of trait constructs such as neuroticism have been shown to be, in part, genetically determined, and many of the risk factors previously believed to be entirely psychosocial have also been shown to be at least partly under genetic influence, including religious and political beliefs, marital difficulties and divorce (e.g. Kendler & Karkowski-Shuman, 1997).

Tunstall challenges us to ‘suggest genes that might plausibly affect suicidal behaviour...which are shared by different Finno-Ugrian-speaking populations but not by less suicide-prone populations’. In a recent genetic study of Slovenian suicides, we have replicated the tryptophan hydroxylase polymorphism previously reported in the Finnish population (further details available from the authors upon request). The same polymorphism has not been replicated in a UK study (Evans et al, 2000), a country less suicide-prone than either Slovenia or Finland.

Tunstall also suggests that the differences between Slovenia and its neighbours result from ‘40 years of separation’, using the analogy of the USSR. Communism under Tito was far less restrictive and deprived, in terms of lifestyle and travel opportunities, than in the former Soviet Republics. In addition, why does the neighbouring country of Croatia, which experienced the same ‘40 years of separation’, consistently report lower suicide rates (Pavlovi & Marui, 2001) if this were the only explanation of the high Slovenian rates?

Finally, Tunstall suggests that a more realistic target for future research would be the detection of genetic influences on impulsivity. This is exactly what we are planning to do.

REFERENCES

Diekstra, R.F.W. (1993) The epidemiology of suicide and parasuicide. Acta Psychiatrica Scandinavica Supplementum, 371, 9-20.[Medline]

Evans, J., Reeves, B., Platt, H., et al (2000) Impulsiveness, serotonin genes and repetition of deliberate self-harm (DSH). Psychological Medicine, 30, 1327-1334.[CrossRef][Medline]

Kendler, K. S. & Karkowski-Shuman, L. (1997) Stressful life events and genetic liability to major depression: genetic control of exposure to the environment. Psychological Medicine, 27, 539-547.[CrossRef][Medline]

Pavlovi, E. & Marui, A. (2001) Suicide in Croatia and in Croatian immigrant groups in Australia and Slovenia. Croatian Medical Journal, 42, 669-672.[Medline]





This Article
Full Text (PDF)
Submit a response
Alert me when this article is cited
Alert me when eLetters are posted
Alert me if a correction is posted
Services
Email this article to a friend
Similar articles in this journal
Similar articles in PubMed
Alert me to new issues of the journal
Download to citation manager
Google Scholar
Articles by Lester, D.
Articles by Farmer, A.
Articles citing this Article
PubMed
PubMed Citation
Articles by Lester, D.
Articles by Farmer, A.


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Psychiatric Bulletin Advances in Psychiatric Treatment All RCPsych Journals