Expanded Chromosomal Microarray Analysis - 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 recommended for patients preferring the highest detection levels possible for fetal evaluations, especially in situations like abnormal ultrasound findings or advanced maternal age. It detects gains and losses of genomic material but has limitations. It won't detect low-level mosaicism, balanced translocations, inversions, or point mutations, making it vital to consider when evaluating genetic conditions and risks.

Special Instructions

Parental samples (5cc whole blood in EDTA tubes) are required alongside signed CMA consent for optimal testing. Maternal contamination studies are automatically performed if maternal samples are included. Other parental studies may incur additional fees. If nudging for additional tests, clinicians are advised to alert clients soon after AOH results are available, detailing UPD testing recommendations and coordinating parental sample collections when necessary.

Limitations

CMA is limited to the detection of gains/losses of genomic material and will not report on changes under 1 Mb. Gains of specific genes without known clinical relevance will not be included either. The test also excludes assessments in various genomic regions such as the Mitochondrial genome and adult-onset disorders for which treatment is unavailable, following ACMG guidelines for reporting.

Test Details

New York Approved