Chromosomal Test For Autism, One Up Over Standard Genetic Testing

A new study published in the journal Paediatrics by the Autism Consortium and Children’s Hospital Boston revealed that a new genetic test called chromosomal microarray analysis (CMA) has the potential to spot autistic genes at a rate more than three times that of a screening considered to be a first-tier test- G-banded karyotype and fragile X testing.

The study involved 933 families who received clinical genetic testing for a diagnosis of autism spectrum disorder from January 2006 to December 2008 and compared results from three clinical genetic tests: G-banded karyotype and fragile X testing and chromosomal microarray analysis.

The tests currently used as a first-tier test for autism only detect 2 percent of the genetic abnormalities that could be behind the development of autism, whereas CMA helps detect autism in about 7 percent of the cases.

“This is the largest study of clinical genetic testing for patients with autism spectrum disorders, and the results clearly show that chromosomal microarray analysis detects genetic abnormalities leading to ASD more often than a standard karyotype and fragile X testing,” said Dr. David Miller of Children’s Hospital Boston.

Currently, in about 4 million births every year in the United States, the U.S. Centers for Disease Control and Prevention put the rate of autism spectrum disorders in American kids at slightly less than 1 percent. This would mean that about 40,000 per year would be expected to have autism spectrum disorders. The potential to better detect autism in these 40,000 cases using CMA would help immensely in better treating these children.

Written by Snigdha for Biomed-ME