Abstract
Duplication 20p or partial trisomy 20 is a rare chromosomal anomaly characterized by duplication of the short arm of chromosome 20, with various clinical abnormalities. Despite complete trisomy 20, which usually leads to prenatal death, partial trisomy 20 can manifest with variable phenotypes, from mild to severe manifestations. Here, we present a rare case of an 8-year-old boy diagnosed with trisomy 20, epilepsy with focal seizures of genetic origin, craniosynostosis, type 1 diabetes, and autism spectrum disorder. Duplication 20p is a complex diagnostic and presents a therapeutic challenge due to its diverse clinical manifestations. To succeed in the intricacy of such a unique and challenging case, a comprehensive clinical and genetic assessment must be performed.