3q29 deletion syndrome is caused by a recurrent hemizygous 1.6 Mb deletion on the long arm of chromosome 3. The syndrome is rare (1 in 30,000 individuals) and is associated with mild to moderate intellectual disability, increased risk for autism and anxiety, and a 40-fold increased risk for schizophrenia, along with a host of physical manifestations. However, the disorder is poorly characterized, the range of manifestations is not well described, and the underlying molecular mechanism is not understood. We designed the Emory 3q29 Project to document the range of neurodevelopmental and psychiatric manifestations associated with 3q29 deletion syndrome. We will also create a biobank of samples from our 3q29 deletion carriers for mechanistic studies, which will be a publicly-available resource for qualified investigators. The ultimate goals of our study are three-fold: first, to improve management and treatment of 3q29 deletion syndrome. Second, to uncover the molecular mechanism of the disorder. Third, to enable cross-disorder comparison with other rare genetic syndromes associated with neuropsychiatric phenotypes. We will ascertain study subjects, age 6 and older, from our existing registry ( 3q29deletion.org ). Participants and their families will travel to Atlanta, GA for phenotypic assessments, with particular emphasis on evaluation of anxiety, cognitive ability, autism symptomatology, and risk for psychosis via prodromal symptoms and syndromes. Evaluations will be performed using standardized instruments. Structural, diffusion, and resting-state functional MRI data will be collected from eligible study participants. We will also collect blood from the 3q29 deletion carrier and participating family members, to be banked at the NIMH Repository and Genomics Resource (NRGR). The study of 3q29 deletion has the potential to transform our understanding of complex disease. Study of individuals with the deletion may provide insights into long term care and management of the disorder. Our project describes the protocol for a prospective study of the behavioral and clinical phenotype associated with 3q29 deletion syndrome. The paradigm described here could easily be adapted to study additional CNV or single gene disorders with high risk for neuropsychiatric phenotypes, and/or transferred to other study sites, providing a means for data harmonization and cross-disorder analysis.

Objective: The goal of this study was to evaluate symptoms of pediatric feeding disorder in a sample of individuals with 3q29 deletion syndrome (3q29Del). Previous research has found that individuals with 3q29Del may experience elevated feeding concerns in early childhood; however, the specificity of these feeding concerns is not well understood. Methods: We compared individuals with 3q29Del (N = 83) with controls (N = 59) using an 11-item survey that assessed commonly reported symptoms associated with pediatric feeding disorders. An exploratory analysis also examined individuals with 3q29Del with and without a comorbid global developmental delay (GDD) or an autism spectrum disorder diagnosis. Results: Caregivers of 3q29Del cases reported higher incidences of feeding concerns on 10 of the 11 items included in the survey. This included statistically significant differences in food refusal behaviors, rejection of 1 or more food groups, and a history of failure to thrive. Parents of children with comorbid GDD were more likely to report concerns regarding food selectivity and problem behaviors during mealtime. Conclusion: The results suggest individuals with 3q29Del experience increased symptoms of pediatric feeding disorder that may require targeted evaluation and intervention for optimal outcomes. Future research should include a more thorough multidisciplinary evaluation to further elucidate symptom severity and optimal treatment strategies.