Diagnosis
FISH Testing
FISH or fluorescent in situ hybridization testing is the most effective method to diagnose Williams syndrome. It is a form of specialized chromosome analysis that makes use of specially drawn elastin probes. During the procedure, the doctor needs to take a 5-ml blood sample from the child or infant with suspected symptoms. If the result shows two elastin gene copies with one on each chromosome 7, it can be a possible sign of the disorder. It might take a few weeks for the samples to be analyzed in the lab. [8]
