I would not say that it is helpful to diagnose autism - there are plenty of Fragile X patients that do not fit autism criteria, it is that Fragile
X and autism characteristics are often co-morbid....This chormosome deletion is
linked to sleep apnea -like symptomsin older children with ASD's
Diagnosis of autism is done only based on behaviors, not genetics, genetics are tested to rule out (or in) underlying genetic abnormalities.