Home
HelpTest Code LAB3621 Family Study FISH
Clinical System Name
Family Study FISH
Synonyms
CH FAMS
Description
This test is appropriate for testing of parents and siblings of a child with an uncertain or abnormal result by traditional cytogenetic testing (karyotype, FISH) or chromosomal microarray (SNP microarray, array CGH). Based on the results of the child's testing, one of the following cytogenetic follow-up tests can be performed: SNP array, interphase or metaphase FISH, qPCR, or limited karyotype. The appropriate follow-up test is typically indicated on the child's test report.
Be sure to review the original proband report to determine if a new sample is also required from the proband in addition to the family member to complete FISH testing. If a new sample is required, please also order Proband Control (LAB3682) for a no charge sample collection from the proband.
Please contact the Laboratory Genetic Counselors (987-5400) if you have questions.
Sample Requirements
Specimen: Whole Blood
Container(s): Lavender/EDTA AND Dark Green/Sodium Heparin (no serum separator)
Preferred Vol: 3-5 mL per tube
Minimum Vol: TWO tubes: Lavender/EDTA and Dark Green/Sodium Heparin (no gel separator), 3 mL PER TUBE
Note: Keep sample at room temperature; deliver to the lab promptly. Samples received after 3 pm will be set up the following day.
Note: DNA is not an acceptable specimen type
Processing Instructions
Reject due to: Collected in microtainer. Extracted DNA
Spin: N
Aliquot: N
Temp: RT
Note: Lavender/EDTA tube only for parental SNP microarray and qPCR is acceptable.
Storage location: Days: Transport specimen, requistion, and labels to 4th floor Cytogenetics (station #181).
Eves/Nights: Store specimen, copy of requisition, and labels in the Cytogenetics box in CPA.
Off-site collection: Keep sample at room temperature. Transport to Seattle Children's Lab promptly. Samples received after 3 pm will be set up the following day.
Stability
| Temperature | Time |
|---|---|
| Room temp | 3 days |
| Refrigerated | No |
| Frozen | No |
Availability
| Test | STAT | Performed | TAT |
|---|---|---|---|
| Parental FISH studies | N | daily | 30 days* |
* delays could occur due to FISH probe availability or if FISH probes require a custom order
Performing Laboratory
Seattle Children's Hospital
Department
Department: Cytogenetics Laboratory
Phone number: 206-987-3961
Lab Client Services: 206-987-2617, labclientservices@seattlechildrens.org
Lab Genetic Counselors: LabGC@seattlechildrens.org
CPT Codes
Determined by test requested - contact Lab Client Services for appropriate CPTs.
Methodology
Method: Interphase fluorescence in situ hybridization (FISH) or metaphase FISH
Clinical Utility
Chromosomes are the packages within cells that contain a person’s genetic information (called “genes” or “DNA”). This genetic information tells a person’s body how to develop and function properly. Gains (duplications) or losses (deletions) result in extra or missing copies of genetic material. These types of changes in a person’s chromosomes may be associated with known genetic conditions or may cause problems with health and development, such as birth defects or cognitive impairment.
This test is appropriate for testing of parents and siblings of a child with an uncertain or abnormal result by traditional cytogenetic testing (karyotype, FISH) or chromosomal microarray (SNP microarray, array CGH). Based on the results of the child’s testing, one of the following cytogenetic follow-up tests can be performed: SNP array, interphase or metaphase FISH, qPCR, or limited karyotype. The appropriate follow-up test is typically indicated on the child’s test report.
Requisition
Special Instructions
Test request form should be completed by the ordering physician to include the proband's name and designate the familial relationship to the proband. Please provide a copy of the family history (pedigree) if available (Cytogenetics Laboratory Fax # 206-987-3840). Follow-up test options (recommendations are listed in the proband's report) are SNP array, FISH, limited karyotype, qPCR, or as determined by the Cytogenetics Laboratory.