Browsing by Subject "geeni-ympäristö -vuorovaikutus"

Aims. There is a growing body of research indicating that childhood experiences interact with genetic vulnerabilities in the development of depression. Parent-child relationship quality has been shown to have a critical role in the development of depression later in life. Moreover, research has shown that the quality of parenting can also have long-term and persistent effects on various neurobiological systems, such as the hypothalamic-pituitary-adrenal (HPA) axis. Indeed, the impaired function of HPA axis has been the most consistently found association with depression. This makes genes related to HPA axis regulation of particular interest to researchers. One possible candidate gene is FK506 binding protein 51 (FKBP5) gene, which has been shown to interact with adverse childhood experiences in predicting future risk of depression. This study examines whether perceived quality of parent-child relationship predicts depressive symptoms in adulthood and whether this association is moderated by the FKBP5 polymorphisms. Methods. This study is part of The Helsinki Birth Cohort Study. Total of 1 667 subjects completed a psychological questionnaire in 2004, including the Beck Depression Inventory (21 item, BDI) and the Parental Bonding Instrument (25 item, PBI). This study utilised the three factor structure of PBI; care, denial of psychological autonomy and encouragement of behavioral freedom, which were measured separately for mother and father. The study looked at three FKBP5 gene polymorphisms: rs1360780, rs9394309 and rs9470080 extracted from the genome-wide data genotyped with modified Illumina 610k array. The study utilised two models 1 and 2; model 1 adjusted for age and gender and additionally model 2 adjusted for childhood and adulthood socioeconomic status (SES) as well as separation experiences. Results and conclusions. As hypothesised and in line with previous studies the quality of parenting predicted depressive symptoms in adulthood. Participants, who perceived having received more care and encouragement of behavioral freedom reported fewer depressive symptoms. Whereas denial of psychological autonomy resulted in reporting more depressive symptoms. None of the polymorphisms predicted depressive symptoms. More importantly, this is the first study to show that FKBP5 polymorphisms modify the relationship between perceived mother-child relationship and depressive symptoms. Among participants with two minor alleles, perceived lack of maternal care and maternal denial of psychological autonomy were most strongly associated with more depressive symptoms. Participants with one minor allele had similar results. Whereas among participants with two major alleles, perceived parenting had a smaller effect on the amount of depressive symptoms. These findings indicate that in addition to adverse experiences and traumas, also deficiencies in parenting can predispose to depression depending on the amount of minor alleles in FKBP5 polymorphisms.