Chromosomal rearrangements are structural anomalies that affect chromosomal architecture and can impact gene expression, genomic imprinting, or even generate de novo gene fusions, as seen in hematological chromosomal aberrations. Chromosomal rearrangements can be associated with syndromes causing neurodevelopmental delay, autism spectrum disorder, and variable dysmorphic features. This article presents the clinical and molecular characteristics of a 2-year-old male child with neurodevelopmental delay who was diagnosed with a chromosomal rearrangement due to a 15q24 duplication (dup15q24). The 15q24 locus presents controversy between the phenotype associated with duplication and deletion, thus posing a challenge in differential diagnosis for both. The phenotypes of autism spectrum disorder and pediatric patients with language delay should be evaluated by a multidisciplinary team comprising genetics, pediatrics, and pediatric neurology to shorten the diagnostic odyssey for patients with rare diseases and to impact the quality of life of the patient and their family.
Keywords: Gene duplication; autism spectrum disorder; chromosome 15q; comparative genomic hybridization; global developmental delay; intellectual disability; language development disorders.