Reflex testing is a stepwise, genome-wide assessment providing the highest diagnostic potential for your patients with neurodevelopmental disorders. Testing begins with FirstStepDx PLUS, with or without Fragile X syndrome testing, and NextStepDx PLUS is automatically initiated if the first-tier testing is non-diagnostic.
Chromosomal microarray can detect deletions and duplications (copy number variants) across the genome, which are common causes of autism spectrum disorder and developmental delay.
This testing is designed to quantify the CGG trinucleotide repeat in the FMR1 gene. When expanded, this repeat causes >99% of cases of fragile X syndrome.
Whole exome sequencing analyzes all protein-coding regions of over 20,000 genes (exome) utilizing next-generation sequencing technologies. While the exome constitutes only 1-2% of the genome, 85% of all disease causing mutations are located there.
The American Academy of Pediatrics, the American Academy of Neurology, and the American College of Medical Genetics & Genomics all recommend chromosome microarray as a first-tier test and whole exome sequencing as a first- or second-tier test for individuals with a neurodevelopmental disorder.