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  • Test code: 08134
  • Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit
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Invitae T-B+NK+ Severe Combined Immunodeficiency (SCID) Panel

Test description

The Invitae T-B+NK+ Severe Combined Immunodeficiency (SCID) Panel analyzes 6 genes that are associated with T-B+NK+ severe combined immunodeficiency. Genetic testing of these genes may confirm a diagnosis and help guide treatment and management decisions. Identification of disease-causing variants provide accurate risk assessment and carrier status for at-risk relatives.

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Primary panel (6 genes)

CD247 CD3D CD3E CORO1A IL7R PTPRC

T-cell negative, B-cell positive, NK-cell positive severe combined immunodeficiency (SCID) including:



Gene Disorder Protein name Protein symbol
CD247 CD3ζ deficiency CD3-zeta CD3-zeta
CD3D CD3δ deficiency CD3-delta CD3-delta
CD3E CD3ε deficiency CD3-epsilon CD3-epsilon
CORO1A Coronin-1A deficiency coronin-1A CORO1A
IL7R IL7Rα deficiency interleukin 7 receptor alpha IL-7RA
PTPRC CD45 deficiency CD45 CD45

T-B+NK+ severe combined immunodeficiency (SCID) is an infantile-onset primary immunodeficiency that presents in blood with dysfunction of T-cells, while B-cell and NK-cell levels remain normal, although non-functional. SCID is characterized by recurrent, overwhelming viral, bacterial and fungal infections and failure to thrive, which if untreated often lead to early death. The onset of manifestations is early, often in the first months of life, and before the age of 6 months, SCID patients often develop chronic diarrhea, interstitial pneumonia and therapy-resistant mucocutaneous candidiasis.

Gene % of T-B+NK+ SCID cases attributed
CD247 <1%
CD3D ~14%
CD3E <1%
CORO1A <1%
IL7R ~85%
PTPRC <1%

All causes of T-B+NK+ severe combined immunodeficiency are inherited in an autosomal recessive manner.

T-B+NK+ SCID accounts for approximately 13% of all cases of SCID.The estimated incidence of T-B+NK+ SCID in the US is approximately 1:430,000, based upon data from universal newborn screening.

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence in the transcript listed below. In addition, analysis covers the select non-coding variants specifically defined in the table below. Any variants that fall outside these regions are not analyzed. Any specific limitations in the analysis of these genes are also listed in the table below.

Based on validation study results, this assay achieves >99% analytical sensitivity and specificity for single nucleotide variants, insertions and deletions <15bp in length, and exon-level deletions and duplications. Invitae's methods also detect insertions and deletions larger than 15bp but smaller than a full exon but sensitivity for these may be marginally reduced. Invitae’s deletion/duplication analysis determines copy number at a single exon resolution at virtually all targeted exons. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. Certain types of variants, such as structural rearrangements (e.g. inversions, gene conversion events, translocations, etc.) or variants embedded in sequence with complex architecture (e.g. short tandem repeats or segmental duplications), may not be detected. Additionally, it may not be possible to fully resolve certain details about variants, such as mosaicism, phasing, or mapping ambiguity. Unless explicitly guaranteed, sequence changes in the promoter, non-coding exons, and other non-coding regions are not covered by this assay. Please consult the test definition on our website for details regarding regions or types of variants that are covered or excluded for this test. This report reflects the analysis of an extracted genomic DNA sample. In very rare cases, (circulating hematolymphoid neoplasm, bone marrow transplant, recent blood transfusion) the analyzed DNA may not represent the patient's constitutional genome.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
CD247 NM_198053.2
CD3D NM_000732.4
CD3E NM_000733.3
CORO1A* NM_007074.3
IL7R NM_002185.3
PTPRC NM_002838.4

CORO1A: Deletion/duplication and sequencing analysis is not offered for exon 11 (NM_007074.3).