Genome-wide association study identifies 30 obsessive-compulsive disorder associated loci.

Obsessive-compulsive disorder (OCD) affects ~1% of the population and exhibits a high SNP-heritability, yet previous genome-wide association studies (GWAS) have provided limited information on the genetic etiology and underlying biological mechanisms of the disorder. We conducted a GWAS meta-analysis combining 53,660 OCD cases and 2,044,417 controls from 28 European-ancestry cohorts revealing 30 independent genome-wide significant SNPs and a SNP-based heritability of 6.7%. Separate GWAS for clinical, biobank, comorbid, and self-report sub-groups found no evidence of sample ascertainment impacting our results. Functional and positional QTL gene-based approaches identified 249 significant candidate risk genes for OCD, of which 25 were identified as putatively causal, highlighting WDR6, DALRD3, CTNND1 and genes in the MHC region. Tissue and single-cell enrichment analyses highlighted hippocampal and cortical excitatory neurons, along with D1- and D2-type dopamine receptor-containing medium spiny neurons, as playing a role in OCD risk. OCD displayed significant genetic correlations with 65 out of 112 examined phenotypes. Notably, it showed positive genetic correlations with all included psychiatric phenotypes, in particular anxiety, depression, anorexia nervosa, and Tourette syndrome, and negative correlations with a subset of the included autoimmune disorders, educational attainment, and body mass index.. This study marks a significant step toward unraveling its genetic landscape and advances understanding of OCD genetics, providing a foundation for future interventions to address this debilitating disorder.

Effects of child-caregiver ratio on the interactions between caregivers and children in child-care centers: an experimental study.

To investigate the effects of child-caregiver ratio on the quality of caregiver-child interaction in child-care centers, 217 caregivers (ages 18-56 years) from 64 child care centers were observed during two structured play episodes: one with a group of three children and one with a group of 5 children. As predicted, a child-caregiver ratio of 3:1 produced a significantly higher quality of caregiver-child interaction than a ratio of 5:1 and particularly for younger children. Significant and meaningful effects were found for both the interactive behaviors of the caregivers and the children's well-being and cooperation. Significant correlations with caregiver-child interaction during lunchtime and throughout the remainder of the morning confirmed the ecological validity of the caregiver-child interactions observed during structured play episodes.