Williams Syndrome Association Ireland

Diagnosing WS

How is Williams Syndrome diagnosed?

Many individuals with Williams Syndrome remain undiagnosed or are diagnosed at a relatively late age. This is of concern since individuals with Williams Syndrome can have significant and possibly progressive medical problems. When the characteristics of Williams Syndrome are recognised, referral to a clinical geneticist for further diagnostic evaluation is appropriate. The clinical diagnosis can be confirmed by a blood test. The technique known as fluorescent in situ hybridisation (FISH), a diagnostic test of the DNA, detects the elastin deletion on chromosome #7 in 95% to 98% of individuals with Williams Syndrome.