Childhood trajectories of emotional and behavioral difficulties are related to polygenic liability for mood and anxiety disorders

ABSTRACT Background Symptoms related to mood and anxiety disorders often present in childhood and adolescence. Some of the genetic liability for mental disorders, and emotional and behavioral difficulties seems to be shared. Yet, it is unclear how genetic liability for mood and anxiety disorders influence trajectories of childhood emotional and behavioral difficulties, and if specific developmental patterns associate with higher genetic liability for these disorders. Methods This study uses data from a genotyped sample of children ( n = 54,839) from the Norwegian Mother, Father and Child Cohort Study (MoBa). We use latent growth models (1.5-5 years) and latent profile analyses (1.5-8 years) to quantify childhood trajectories and profiles of emotional and behavioral difficulties and diagnoses. We examine associations between these trajectories and profiles with polygenic scores for bipolar disorder (PGS BD ), anxiety (PGS ANX ), depression (PGS DEP ), and neuroticism (PGS NEUR ). Results Associations between PGS DEP , PGS ANX and PGS NEUR , and emotional and behavioral difficulties in childhood were developmentally stable rather than age specific. Higher PGS ANX and PGS DEP were associated with steeper increases in behavioral difficulties across early childhood. Latent profile analyses identified five profiles. All PGS were associated with probability of classification into profiles characterized by some form of difficulties (vs. a normative reference profile), but only PGS BD was uniquely associated with a single developmental profile. Conclusions Our findings indicate that genetic risk for mood disorders and related traits contribute to a more rapidly increasing and higher overall burden of emotional and behavioral difficulties across early and middle childhood, with some indications for disorder-specific profiles. These findings of associations between childhood trajectories and symptom profiles and genetic and clinical susceptibility for mental disorders, may form the basis for more targeted early interventions.