ABSTRACT
INTRODUCTION: Brain-derived neurotrophic factor (BDNF) polymorphisms have been examined for their contribution toward depression with equivocal results. More homogeneous phenotypes might be used to improve our understanding of genetic liability to depression. The aim of our study was to (a) test for an association between the BDNF Val66Met polymorphism and childhood-onset melancholic depression and (b) to examine the interactive effects of stressful life events (SLE) and the Val66Met polymorphism on the risk of childhood-onset melancholic depression. MATERIALS AND METHODS: A total of 583 depressed probands were involved in this study (162 of the melancholic subtype). Diagnoses were derived through the Interview Schedule for Children and Adolescents - Diagnostic Version and life event data were collected using an Intake General Information Sheet. RESULTS: Overall, 27.8% of the participants fulfilled the criteria for melancholy. In the melancholic group, the proportion of females was higher (53.1%), although there were more males in the overall depressed sample. We detected no significant differences in genotype or allele frequency between the melancholic and the nonmelancholic depressed group. The BDNF Val66Met polymorphism and SLE interaction was not significantly associated with the melancholy outcome. CONCLUSION: In our study, females were more prone to developing the early-onset melancholic phenotype. To our knowledge, this is the first study to investigate the differentiating effect of the genotype and the G×E interaction on the melancholic phenotype in a large sample of depressed young patients. We did not find an association between the melancholic subtype of major depression and the BDNF genotype and SLE interaction in this sample, which is representative of the Hungarian clinic-referred population of depressed youths.
Subject(s)
Brain-Derived Neurotrophic Factor/genetics , Depressive Disorder, Major/genetics , Depressive Disorder, Major/psychology , Life Change Events , Adolescent , Age of Onset , Child , Depressive Disorder, Major/epidemiology , Female , Humans , Hungary/epidemiology , Male , Methionine/genetics , Polymorphism, Single Nucleotide , Valine/geneticsABSTRACT
BACKGROUND: Oxytocin (OXT) and prolactin (PRL) are neuropeptide hormones that interact with the serotonin system and are involved in the stress response and social affiliation. In human studies, serum OXT and PRL levels have been associated with depression and related phenotypes. Our purpose was to determine if single nucleotide polymorphisms (SNPs) at the loci for OXT, PRL and their receptors, OXTR and PRLR, were associated with childhood-onset mood disorders (COMD). METHODS: Using 678 families in a family-based association design, we genotyped 16 SNPs at OXT, PRL, OXTR and PRLR to test for association with COMD. RESULTS: No significant associations were found for SNPs in the OXTR, PRL, or PRLR genes. Two of three SNPs 3' of the OXT gene were associated with COMD (p≤0.02), significant after spectral decomposition, but were not significant after additionally correcting for the number of genes tested. Supplementary analyses of parent-of-origin and proband sex effects for OXT SNPs by Fisher's Exact test were not significant after Bonferroni correction. CONCLUSIONS: We have examined 16 OXT and PRL system gene variants, with no evidence of statistically significant association after correction for multiple tests.
Subject(s)
Mood Disorders/genetics , Oxytocin/genetics , Polymorphism, Single Nucleotide , Prolactin/genetics , Adolescent , Age of Onset , Child , Family , Female , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Humans , Male , Mood Disorders/epidemiology , Receptors, Oxytocin/genetics , Receptors, Prolactin/geneticsABSTRACT
The authors summarize their experiences in research organization accumulated during 13 years. At first they outline preliminary studies which are prerequisites of high prestige international grants. Then they describe the huge administrative apparatus dedicated - besides skilled professionals - for the construction and organization of the research, the management, continuous checking and evaluation of data in such a multisite study. Finally, they report on the scientific results obtained after 13 years of hard work.
