Abstract
The human 16p11.2 BP4-BP5 region, composed of low-copy repeats, is prone to mediating recurrent copy number variations that increase the risk of neurodevelopmental disorders. Compared with 16p11.2 deletion variants, duplication variants have lower penetrance and higher phenotypic heterogeneity. Due to limited perinatal data, early phenotypes warrant further investigation. We report the case of a neonate with seizures, microcephaly, and neurodevelopmental delay whose parents were phenotypically normal. Whole-exome sequencing revealed a 200.15-kb duplication in 16p11.2 seq[GRCh38]dup(16)(p11.2-p11.2) (chr16:29,963,728-30,168,686) in the proband and his mother, which was confirmed via quantitative polymerase chain reaction. This case highlights the potential link between 16p11.2 duplications and neonatal neurodevelopmental disorders, emphasizing the need for genetic counseling in affected families.