CLSI eNews - 13 July 2005 (Plain Text Version)

Return to Graphical Version | Search back issues | Print all articles

In this issue:
Note on printing single articles: Each selected individual article will appear at the bottom of this screen...please scroll down to view/print the selected article.

News
Executive Vice President's Message
Standards in Action
Volunteer Focus
Press Releases
Standards Status
Vote and Deadlines
New CLSI Documents
Terminology Focus
Events and Exhibits
Upcoming Events
Calendar of Meetings
Participation in CLSI
Volunteer
New and Sustaining Members
Update Your Subscription

Standards in Action

Fluorescence In Situ Hybridization (FISH) Methods for Medical Genetics (MM7-A)
UVA Health System, Mayo Clinic weigh in on importance of popular CLSI cytogenics guideline to their facilities

Fluorescence in situ hybridization (FISH) technology is a mapping technique that uses fluorescent molecules to locate specific chromosomes, or DNA/RNA sequences along a chromosome. The method can detect cytogenetic aberrations that are not readily evident by standard cytogenetic banding analyses. Used by laboratory directors, surgical pathologists, medical technologists, geneticists, oncologists, and other laboratory personnel, CLSI guideline MM7-A, Fluorescence In Situ Hybridization (FISH) Methods for Medical Genetics; Approved Guideline, is the accepted reference guideline on FISH assays in clinical practice.

According to Kathryn Sudduth, CLSup,CLSp(CG), Past President of the Association of Genetic Technologists, and currently Cytogenetics Laboratory Manager for the University of Virginia Health System, “The use of FISH probes in the Clinical Genetics Lab is one of the fastest growing technologies today (and) the MM7-A guideline has provided a consistent means for the laboratory practitioner to prepare these tools for implementation in the clinical arena.”

FISH has grown popular because it makes it possible to render medical genetic determinations, identify chromosomal abnormalities, and amplify genes both accurately and in a brief period of time. At the Mayo Clinic, MM7-A has been vital to the work of Gordon Dewald, PhD, FACMB, “since the very day it was published. We both use this document with our commercial probes, and make home-brew probes ourselves. MM7 works for both.”

In both his former position as Chair of Mayo’s Division of Laboratory Genetics, and his current post as Co-Director of the Cytogenetics Laboratory at Mayo, Dewald’s work is largely focused around FISH—and, in turn, he says, MM7-A.

“I have several copies of this book,” Dewald says. “I also have an electronic version—or two. To this day, the MM7-A guideline is the best—it’s the only reference that describes how to validate FISH assays in clinical practice.”

So at a world-renowned facility such as the Mayo Clinic, just who uses CLSI’s MM7-A guideline?

According to Dewald, “A number of people—in a number of different positions.

"Certainly the person in charge of our cytogenic training program—the MM7-A is essential for training in this area. Then of course the development technologists whose job is to develop FISH probes—they all use this format—this methodology. We also have a supervisor in the FISH area who is very familiar with this document.”

MM7-A also plays a large role in Mayo’s quality assurance program: “There are validation criteria for clinical practice through proficiency testing, and this document makes recommendations for proficiency testing,” Dewald says. “We have quality assurance specialists who are following those guidelines. No question about it.”

Overall, Sudduth notes, the methodology outlined in CLSI document MM7-A has made more genetic information available to the clinician, particularly in the area of hematological diseases. This is because FISH probes “allow a visual assessment of specific genetic regions.” Scientists can now view different specific fusion or break-apart configurations.

“By having a standard way of establishing specificity and sensitivity, the laboratory can provide a result which is consistent and meaningful to the clinician for diagnosis and prognosis.”

Standards in Action is a new eNews feature which highlights the practical ways in which CLSI standards and guidelines are being used each day in order to contribute to the organization's mission of improving the quality of health care worldwide.