Known mtDNA Variant(s) by NGS

Casandra

Casandra Test Code GE29607Version 1 (DRAFT)

Performing Lab

Lab GeneDxLab Test ID 453

Known mtDNA Variant(s) by NGS

Clinical Use

Use

This test is designed to detect a specific, previously identified mitochondrial DNA (mtDNA) variant(s) in a patient, using next‑generation sequencing to assess the entire mitochondrial genome for the known variant(s) of interest in comparison to the revised Cambridge Reference Sequence (rCRS, NC_012920). It is particularly useful when there is a known familial or index-case variant and can help confirm its presence and heteroplasmy level in additional individuals.

Special Instructions

Report results for known mtDNA variant(s) using genomic DNA from tissue biopsy, blood in EDTA, or buccal samples (per code 453). Ensure to follow the GeneDx specimen requirements for submission of DNA from acceptable specimen types.

Limitations

Lower limit of heteroplasmy detection is 2%, so variants present below this threshold may not be reliably detected. The test is limited to detection of known variant(s); it may not detect novel or additional variants outside the queried position(s).

Test Details

Methodology

NGS

Biomarkers

Amplifies and sequences the entire mitochondrial genome using next‑generation sequencing, comparing it to the revised Cambridge Reference Sequence (NC_012920) to detect the known mtDNA variant(s) with a heteroplasmy detection limit of approximately 2%.

mtDNA sequencing • Targeted