Casandra

Casandra Test Code BA19058Version 1 (DRAFT)

Performing Lab

Lab Baylor GeneticsLab Test ID 8676CPT Codes 81228, 81265, 88235, 88261, 88291

CMA-Expanded and Limited Karyotype - Prenatal - CVS

Clinical Use

Use

CMA-Expanded utilizes array-based comparative genomic hybridization (aCGH) and contains 400K oligonucleotides to offer exon-by-exon copy number analysis of over 1,700 genes. This test is essential for identifying copy number changes and is recommended for both providers and patients wishing for thorough fetal evaluations. Implications include enhanced detection capabilities, particularly for conditions such as triploidy and abnormalities detected via prenatal ultrasound. This test serves those at advanced maternal age or with a history of chromosome abnormalities, focusing on providing the highest level of detection for significant genetic conditions linked to fetal development.

Special Instructions

For optimal results, parental samples (5 cc whole blood in EDTA tubes) are necessary, and maternal cell contamination studies will be conducted if maternal blood is provided. In instances where interpretation relies on parental studies, these are performed to clarify significance. Certain high-risk results may necessitate additional testing at a fee-for-service basis, and UPD analysis can be requested for specific findings. Baylor Genetics keeps the client informed regarding significant results and available further testing options.

Limitations

The test will not detect low-level mosaicism, balanced translocations, inversions, or point mutations. Additionally, gains and losses under specific threshold sizes, particularly those involving the mitochondrial genome or those associated with adult-onset disorders without available treatment, will not be reported. It is important to note that detected abnormalities may require further testing, including examination for parental balanced rearrangements and reporting guidelines will adhere to the American College of Medical Genetics standards.

Test Details

Methodology

Chromosomal / Cytogenetics (FISH)

Biomarkers

2 components

Primary Component • FISHComparative Genomic Hybridization • FISH

Result Turnaround Time

7-10 days

Specimen

Tissue (Fresh)

Volume

15 mg

Minimum Volume

15 mg

Container

sterile tissue culture media

Collection Instructions

Collect 15+ mg CVS in sterile tissue culture media.

Storage Instructions

Ship the sample at room temperature to the laboratory by overnight express. Specimen should arrive in the laboratory within 48 hrs of sample date. Specimen cannot be frozen.