Chromosomal microarray analysis (CMA) is a powerful genetic testing tool that is used to detect chromosomal abnormalities or chromosomal DNA changes at a high resolution. CMA detect chromosomal abnormalities of various sizes, ranging from small deletions or duplications of a few kilobases to larger structural changes involving entire chromosomes that result in certain genetic disorders or developmental disabilities which are not detected by traditional methods.
CMA is playing a potential role in genetic diagnostics in identification of the underlying genetic cause of intellectual disabilities, developmental delays, congenital anomalies, autism spectrum disorders, and other conditions where genetic factors are involved with higher specificity and sensitivity.
What does CMA detect?
CMA detects various types of chromosomal abnormalities, including:
- Copy number variations (CNVs): Deletions, duplications, rearrangements, where a specific region of the genome is duplicated or deleted or rearranged. Also, can identify structural chromosomal abnormalities, such as translocations, where genetic material is exchanged between two non-homologous chromosomes.
- Loss of heterozygosity (LOH): LOH refers to the loss of one copy of a particular gene or chromosome, resulting in a higher risk for certain genetic conditions or cancers.
- Uniparental disomy (UPD): UPD occurs when an individual inherits two copies of a chromosome or a portion of a chromosome from one parent, instead of one copy from each parent. UPD can lead to various health conditions, depending on the chromosome involved.
When Is The CMA Recommended?
- Developmental delay or intellectual disability
- Multiple congenital anomalies
- Autism spectrum disorder (ASD)
- Unexplained seizures or epilepsy
- Family history of known chromosomal abnormality Prenatal diagnosis
- Recurrent pregnancy loss or stillbirth
- Positive family history of known chromosomal abnormality