Developmental trajectories for young children with 16p11.2 copy number variation

Area of Science:

• Neuroscience
• Genetics
• Developmental Psychology

Background:

• Copy number variation (CNV) at the 16p11.2 locus is linked to varied neurodevelopmental disorders.
• Limited understanding exists regarding the early developmental trajectories and phenotypic emergence associated with 16p11.2 CNVs.

Purpose of the Study:

• To longitudinally investigate the developmental trajectories of cognitive, adaptive, and behavioral domains in children with 16p11.2 BP4-BP5 deletion or duplication.
• To identify distinct developmental pathways and early indicators for specific phenotypes associated with 16p11.2 CNVs.

Main Methods:

• Longitudinal study of 56 children (6 months to 8 years) with 16p11.2 deletion or duplication.
• Diagnostic characterization and dimensional assessments across cognitive, adaptive, and behavioral domains.
• Application of linear mixed modeling and nonparametric analyses to delineate developmental trajectories.

Main Results:

• Children with 16p11.2 deletions exhibited verbal IQ (VIQ) gains but declines in motor and social abilities.
• Children with 16p11.2 duplications showed VIQ gains and consistent development across other domains.
• Distinct early trajectories were observed for deletion carriers (intellectual disability, developmental coordination disorder) and duplication carriers (autism spectrum disorder, intellectual disability).

Conclusions:

• Early developmental trajectories for 16p11.2 CNVs are distinct and predictable.
• Findings offer insights into early functioning and highlight the need for monitoring social, motor, and behavioral aspects.
• Improved treatment planning can result from understanding these specific developmental pathways.