X-linked severe combined immunodeficiency (X-SCID)
Download a Test Requisition Form
You can download the Test Requisition form (106k) in portable document format (.pdf).
About the Disorder | Indication | Specimen l Testing Methodology l Turnaround Time l Cost l CPT Codes l Shipping l Results l Contact Us
About the Disorder
X-SCID typically presents within a few months after birth with persistent viral, bacterial, and fungal infections, lymphocytopenia, growth failure, and thymic hypoplasia. Patients have a low number of T cells, variable number of B cells, low immunoglobulins, and no specific antibodies. X-SCID is caused by a mutation in the common gamma chain gene. This gene, located on the X chromosome at Xq13.1, is composed of eight exons and seven introns and spans approximately 4.2 kilobases. Pathologic mutations have been described in all exons.
Back to Top
Indications
- Confirmation of diagnosis in an at-risk or symptomatic individual
- Carrier identification in females with a family history
- Prenatal diagnosis of an at-risk fetus, after identification of a mutation in a proband (by prior arrangement only).
Back to Top
Specimen
At least 3cc whole blood in purple top (EDTA) tube. Label tube with patient's name, birth date, and date of collection. Buccal swabs are required for analysis in patients who have undergone transplantation and may facilitate DNA isolation in patients undergoing chemotherapy or in individuals with leukopenia. Please call for a free buccal swab collection kit.
Back to Top
Testing Methodology
PCR-based sequencing of entire coding region of the interleukin 2 receptor gamma chain (IL2RG) gene and its intron/exon boundaries.
Sensitivity
Sequencing detects about 99% of mutations in the IL2RG gene in males. In females, test sensitivity is somewhat lower as PCR-based sequencing does not detect large deletions, insertions or rearrangements within a gene.
Back to Top
Turnaround Time
1 month
Back to Top
Cost
- Full gene sequencing
- Known mutation detection (by prior arrangement only)
Please call 513-636-7909 for current pricing.
Back to Top
CPT Codes
83890, 83898 (x4), 83894 (x4), 83891 (x4), 83904 (x16), 83912
Back to Top
Shipping Instructions
Please enclose test requisition with sample. All information must be completed before sample can be processed. The test requisition is available for download as a 63 Kb .pdf file at the top of this page. Place samples in styrofoam mailer and ship at room temperature by overnight Federal Express to arrive Monday through Friday.
Ship to
Cytogenetics and Molecular Genetics Laboratories
3333 Burnet Avenue NRB 1042
Cincinnati, OH 45229
513-636-4474
Back to Top
Results
Results will be reported to the referring physician or genetic counselor as specified on the requisition form.
Back to Top
Contact Us
For additional inquiries, contact us:
Phone 513-636-4474
Fax 513-636-4373
Email moleculargenetics@cchmc.org
Back to Top
