Simplex Autism Spectrum Disorder (ASD), where just one child in a family has the diagnosis, offers a unique window into the complexities of ASD. Unlike familial ASD, simplex cases showcase a fascinating phenomenon: phenotypic heterogeneity. This means children with simplex ASD display a wide range of symptoms, despite a strong genetic link.Data analysis plays a critical role in unraveling this phenotypic mosaic. By studying large cohorts of simplex ASD individuals, researchers can identify patterns in their social challenges, restricted interests, and repetitive behaviors. This data can reveal subgroups within simplex ASD, each potentially linked to specific genetic variations.Understanding these phenotypic variations is crucial. It sheds light on how genetic factors interact with the environment to produce such a diverse spectrum of ASD presentations. This knowledge can pave the way for more targeted therapies tailored to individual phenotypes within simplex ASD