Cytogenetics

CytogeneticsCytogenetics Department

The OSF System Laboratory staffs its own in-house cytogenetics department six days a week, with certified cytogenetic technologists, lab technologists, and a PhD board certified clinical cytogeneticist.

The department performs a variety of specialized tests, which aid clinicians in the diagnosis and treatment of patients with congenital/constitutional or oncological disorders, but occasionally there is a need to send very unique cases to a specialized lab for testing.

Chromosome analysis testing detects abnormalities in the number or structure of the chromosomes and can be performed on a variety of specimen types, without the need for and resulting delay from sending them to an outside facility for processing. 

In-house testing is performed every weekday, as well as occasionally on the weekend, though specimens are accepted any day of the week.

Chromosome analysis tests that we perform include:

  • Blood (for congenital disorders): TAT 14-28 days; (for Stat newborns): Prelim in 48-72 hrs, final in 7 days
  • Bone Marrow or Blood (for hematological disorders): TAT 10-21 days; (for Stat cases): Prelim in 24-48 hrs, final in 7 days

FISH Testing

GF10-DGS PROF_F pos.jpg Fluorescence in situ hybridization (FISH) testing detects specific genetic sequences in human cells, including certain regions of the chromosomes and portions of selected genes.

FISH tests can detect certain types of genetic abnormalities that are too small to be detected by chromosome analysis, and some of the tests can be performed on non-dividing cells, which eliminates cell culture time and allows examination of cells that do not grow well in culture. 

FISH testing can be used to diagnose certain congenital disorders, such as microdeletion syndromes, as well as genetic changes associated with some types of leukemia and cancer. 

A FISH test can also provide additional information that helps predict a patient’s outcome and whether he or she is likely to respond to certain chemotherapy drugs, in cases where a type of cancer has already been diagnosed.

Abnormal cells can be visualized and counted using a  fluorescence microscope.  Abnormalities found in cancer cells include translocation, inversion, deletion, and duplication. 

The result TAT varies on normal cases but can be expedited on stat cases to 1-3 days. A few of the most common FISH tests we perform are:

  • DiGeorge (for deletion of 22q11.2): TAT 3-7 days
  • BCR/ABL Fusion (for Philadelphia chromosome, CML, translocation 9;22): TAT 5-7 days
  • PML/RARA Fusion (for AML M3, translocation 15;17): TAT 5-7 days

Genetic Counseling

Genetic Counseling services are available to a wide range of patients. This includes pre-conception and prenatal genetic counseling when there is a family history of a known or suspected genetic syndrome.

Prenatal genetic counseling is also available for individuals interested in carrier screening, those identified to have ultrasound anomalies or abnormal genetic screening results, and individuals with a  family history of a genetic disorder.

This is done in coordination with the OSF Perinatology Group.

Genetic counseling is also available to patients with a family history of a possible hereditary cancer syndrome, such as hereditary breast and ovarian cancer.

Genetic counselors also work with the cystic fibrosis clinic to provide genetic counseling to those families.

For more information on genetic counseling and the clinics and services offered, visit the Children’s Hospital of Illinois website at www.childrenshospitalofillinois.org.