College of American Pathologists
CAP Committees & Leadership CAP Calendar of Events Estore CAP Media Center CAP Foundation
 
About CAP    Career Center    Contact Us      
Search: Search
  [Advanced Search]  
 
CAP Home CAP Advocacy CAP Reference Resources and Publications CAP Education Programs CAP Accreditation and Laboratory Improvement CAP Members
CAP Home > CAP Reference Resources and Publications > CAP TODAY > CAP TODAY 2005 Archive > No cookbook approach
Printable Version

  "No cookbook approach"

title

 

 

 

cap today

Related articles:
"If DNA doesn’t add up, array CGH steps in"
DNA Samples (PDF document 1,431 K)

September 2005
Feature Story

What does array CGH look like to a practicing medical geneticist?

"From a clinical geneticist’s perspective, microarray analysis allows us to identify children with subtle chromosomal abnormalities that are not detected by available standard techniques—karyotyping or FISH analysis," says Mira Irons, MD, FACMG, interim chief in the Division of Genetics at Children’s Hospital, Boston, who sends occasional samples for array CGH. Among patients seen by a clinical geneticist, approximately 40 percent to 50 percent don’t have a diagnosis. No chromosomal abnormality or metabolic condition can be identified and no syndrome can be diagnosed based on how the child looks. In these patients, Dr. Irons says, array CGH provides an additional tool. She estimates that it can identify an underlying chromosomal abnormality in a few percent of kids being sent to a geneticist for evaluation.

"In my own personal practice, having microarray analysis has allowed me to diagnose a few kids that I have been following with mental retardation of unknown etiology or multiple congenital anomalies of unknown etiology or growth retardation," Dr. Irons says.

She suggests that, as array CGH covers larger sections of the genome, it may replace standard karyotyping. "Clearly it is not there yet," she says. "Doing initial karyotyping is still a geneticist’s first-line test. Depending on the clinical presentation, I might then go to FISH or microarray."

As for cost, she considers array CGH to be like any other expensive test. "You have to weigh the cost of doing the test against the chance of getting a diagnosis and its benefits," she says. The cost of array CGH must also be balanced against the cost of doing many FISH probes or many metabolic tests. "There is no cookbook approach to evaluating children with mental retardation or congenital anomalies or growth problems," Dr. Irons says. "You have to determine the best testing path for that child."


William Check, PhD
 
     
 
 © 2014 College of American Pathologists. All rights reserved. | Terms and Conditions | CAP ConnectFollow Us on FacebookFollow Us on LinkedInFollow Us on TwitterFollow Us on YouTubeFollow Us on FlickrSubscribe to a CAP RSS Feed