Chromosomal Microarray(CMA315k) - Affymetrix Cytoscan Optima With MCC

Chromosomal Microarray (CMA315K) – Affymetrix CytoScan™ Optima With MCC

Overview
Chromosomal Microarray (CMA315K) using the Affymetrix CytoScan™ Optima platform is an advanced genomic test designed to detect chromosomal abnormalities such as microdeletions, microduplications, aneuploidies, and regions of homozygosity across the entire genome. This test includes Maternal Cell Contamination (MCC) analysis to ensure accurate interpretation of prenatal samples by identifying and excluding maternal DNA contamination. The CytoScan Optima array contains approximately 315,000 genomic markers, including copy number and SNP probes for comprehensive chromosomal analysis.

Why is this test performed?

• Evaluation of fetal structural abnormalities detected on ultrasound
• Prenatal diagnosis of chromosomal disorders
• Investigation of developmental delay or congenital anomalies
• Detection of clinically significant copy number variations (CNVs)
• Identification of regions of absence of heterozygosity (AOH) or uniparental disomy (UPD) when applicable
• Confirmation of suspected chromosomal abnormalities

What does it detect?

• Microdeletions and microduplications
• Whole chromosome gains or losses (aneuploidy)
• Copy Number Variations (CNVs)
• Regions of homozygosity (ROH/AOH)
• Unbalanced chromosomal rearrangements
• Selected low-level mosaic abnormalities (depending on size and proportion)

Sample Required

• Chorionic Villus Sample (CVS)
• Amniotic Fluid
• Products of Conception (POC)
• Maternal blood sample (required for MCC analysis)

Technology

• Affymetrix CytoScan™ Optima Array (315K)
• SNP & Copy Number Probe Analysis
• Chromosome Analysis Suite (ChAS) software
• Maternal Cell Contamination (MCC) assessment

Benefits

• Genome-wide high-resolution chromosomal analysis
• Higher diagnostic yield than conventional karyotyping for submicroscopic abnormalities
• Detects abnormalities too small to be identified by routine chromosome analysis
• MCC testing improves the accuracy of prenatal sample interpretation
• Supports informed genetic counseling and pregnancy management

Limitations

This test does not detect:

• Balanced chromosomal rearrangements (balanced translocations or inversions)
• Single-gene (point) mutations
• Very small insertions/deletions below the platform's detection limit
• Low-level mosaicism below the assay sensitivity
• Epigenetic or methylation disorders

Turnaround Time

Approximately 10–21 working days (may vary depending on sample quality and laboratory workflow).