Hyper-IgM Syndrome (HIGM): (CD40LG [TNFSF5] for HIGM1) (Full Gene Sequencing)

Casandra

Casandra Test Code LC03615Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 252435CPT Code 81404

Hyper-IgM Syndrome (HIGM): (CD40LG [TNFSF5] for HIGM1) (Full Gene Sequencing)

Clinical Use

Use

Confirm a clinical diagnosis of HIGM; detect carriers; allow early diagnosis in family members, guiding prophylactic measures

Special Instructions

Informed consent for genetic testing is required. Test orders must include an attestation that the provider has the patient's consent, and in cases where a known mutation can be documented, the physician may prefer to order test 252673. Family tests for known mutations require submitting the result report of the first patient tested in the family if not performed at a LabCorp facility.

Limitations

This DNA sequencing method does not reliably detect mosaic variants, large deletions, large duplications, inversions, or other rearrangements, nor deep intronic variants. It may be affected by allele-dropout, and will not allow determination of the exact number of T/A repeats or microsatellite repeats. It does not enable conclusions regarding whether two heterozygous variants are present on the same or on different chromosome copies.

Test Details

Methodology

NGS (Targeted)

Biomarkers

This test includes sequencing of all coding nucleotides of the CD40LG (TNFSF5) gene, including flanking intronic regions, splice sites, and UTRs. It focuses on confirming clinical diagnosis of HIGM and identifying carriers.

Full Gene Sequencing • Targeted