Multilayered genetic dissection of autism: insights from whole-exome sequencing, molecular karyotyping, and cytogenetic analyses in a small Turkish cohort.

Autism spectrum disorder (ASD) is a neurodevelopmental condition marked by difficulties in social interactions, communication impairments, repetitive behaviors, and restricted interests. A genetic basis for ASD is now well-established. With the availability of high-throughput microarray and sequencing platforms, major advances have been made in our understanding of genetic risk factors. This study assessed the patient records of 62 children diagnosed with ASD or at risk for ASD. Cytogenetics, molecular karyotyping, and whole-exome sequencing (WES) were conducted for these cases. Three likely pathogenic variants were detected in the genes KMT2C, FOXP2, and MAN1B1, each at a rate of 1.6% of total cases. Additionally, variants of uncertain significance (VUS) were found in 13 genes previously associated with ASD. The frequencies of these VUS in total cases were as follows: DLG3-1.6%, MECP2-1.6%, SETD5-1.6%, GRIN1-1.6%, ASXL3-3%, KMT2D - 5%, AP1G1-3%, SPTBN1-3%, TRIP12-1.6%, HCN1-3%, ZNF292-1.6%, and ACSL4-1.6%. We found gene variants in 35% of cases, a rate consistent with previous reports, emphasizing the importance of comprehensive genetic analysis in diagnosing ASD with unclear etiology. This study offers valuable insights into the genetic landscape of ASD within a small cohort and highlights the need for ongoing monitoring and genetic counseling in conditions that present with ASD-like symptoms.