Suicide is a multicausal phenomenon posing a great challenge to medicine and society, yet we still have limited knowledge concerning underlying biochemical, neuroanatomical and genetic factors. Research increasingly points to a role of the serotonergic system, both on the level of suicidal behavior, and such behavioural traits which may serve as important intermedier endophenotypes in suicide research. Although results are conflicting, several studies described an association between the 5-HTTLPR polymorphism and suicide, as well as this polymorphism and certain aggressive traits. Impulsive aggression is also thought to play a major contributory role in suicide. The aim of our research was to investigate the association between the 5-HTTLPR and aggressive traits in depressive patients carrying a higher risk for suicide and healthy controls.

137 major depressive and 164 healthy controls women were recruited. Participants completed the Buss-Durkee Hostility Inventory and were genotyped for 5-HTTLPR. Association of aggressive traits and indeces with 5-HTTLPR genotype in the two groups were analysed using ANCOVA.

Diagnosis and 5-HTTLPR genotype showed a significant association with aggressive traits. The pattern of association was different in the depressed and control groups. The strongest interaction effect between genotype and diagnosis was observable in case of Resentment.

We found a significant association between 5-HTTLPR and several aggressive traits. In case of depressive patients the association was more marked. In depressed women the 5-HTTLPR shows a stronger association with aggressive traits related to aggression turned inward, which may play a role in the background of suicide.

Affective temperaments as measured by the TEMPS-A are known to be associated with 5-HTTLPR, however, this association is valid in case of all scales within the depressive superfactor (depressive, cyclothymic, irritable, anxious). Less attention was paid to the association of items composing these affective temperament scales with the 5-HTTLPR polymorphism. The aim of our study was to investigate the association of TEMPS-A items with the s allele of the 5-HTTLPR.

138 psychiatrically healthy women completed the TEMPS-A questionnaire and were genotyped for 5-HTTLPR. Scores of subjects on the temperament scales, subscales and items were compared in subjects carrying and not carrying the s allele (dominant model) using ANOVA. We selected items with significantly different mean scores between two groups and performed item analysis.

Subjects in the two groups had significantly different scores on the depressive, cyclothymic, irritable and anxious temperament scales. Subjects carrying and not carrying the s allele had significantly different scores on 12 items, 9 of which were retained in a derived 5-HTTLPR phenotype scale after item analysis.

Our data provide further support for the association of affective temperaments with the s allele. Although the cyclothymic temperament shows the strongest association, all temperaments within the depressive superfactor have a similar share in this association. The newly derived 5-HTTLPR Phenotype Scale shows strong association with 5-HTTLPR genotype and phenotype, therefore this scale should be further investigated in relation to psychiatric disorders, pharmacological response, and suicide, as well as psychological traits and temperaments.

Periodicity, cyclicity, and annual rhythms are inherent characteristics of living organisms, and have also been reported for diverse physiological and pathological conditions and phenomena. Season of birth was also associated with central monoamine and monoamine metabolite levels in several studies. Furthermore, several studies indicate a significant effect of season of birth on personality traits and characteristics. A relationship between birth season and novelty seeking has been described and confirmed in several studies. However, affective temperaments have not so far been studied with respect to their association with birth season.

The aim of our present study was to investigate the possible association between affective temperaments and season of birth in a nonclinical sample.

366 university students completed the standardized Hungarian version of the TEMPS-A. Ordinary Least Squares regression was applied to explain the relationship between TEMPS-A subscales and birth season of the respondents.

We found a significant association between temperament scores and birth season in case of the Hyperthymic, Cyclothymic, Irritable and Depressive temperaments, while no significant results emerged for the Anxious temperament.

Our results provide further evidence for an association between season of birth and personality, extending the results to affective temperaments as well. Furthermore, our results can be related to clinical observations concerning the seasonal variation of onset and hospitalization due to affective episodes, thus our results also have clinical significance.

Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset, using a large, international database.

The database includes 4037 patients with a diagnosis of bipolar I disorder, previously collected at 36 collection sites in 23 countries. Generalized estimating equations (GEE) were used to adjust the data for country median age, and in some models, birth cohort. Model-based clustering (mixture analysis) was then performed on the age of onset data using the residuals. Clinical variables in subgroups were compared.

There was a strong birth cohort effect. Without adjusting for the birth cohort, three subgroups were found by clustering. After adjusting for the birth cohort or when considering only those born after 1959, two subgroups were found. With results of either two or three subgroups, the youngest subgroup was more likely to have a family history of mood disorders and a first episode with depressed polarity. However, without adjusting for birth cohort (three subgroups), family history and polarity of the first episode could not be distinguished between the middle and oldest subgroups.

These results using international data confirm prior findings using single country data, that there are subgroups of bipolar I disorder based on the age of onset, and that there is a birth cohort effect. Including the birth cohort adjustment altered the number and characteristics of subgroups detected when clustering by age of onset. Further investigation is needed to determine if combining both approaches will identify subgroups that are more useful for research.