Chromosomal microarray (CMA) is a type of chromosome test that can be done during pregnancy along with an amniocentesis or chorionic villus sampling (CVS), or can be done for patients who are suspected of having an underlying genetic syndrome.

CMA can detect if there are small bits of missing (deletion) or extra (duplication) chromosome material that are too small to be detected by traditional chromosome analysis (karyotype). Extra (trisomy) or missing (monosomy) chromosomes can still be detected with CMA, but it may not be able to find chromosome translocations (when two pieces of chromosome break off and switch spots) or inversions (when a piece of chromosome breaks off and turns upside down).

There are over 150 genetic conditions that are caused by chromosome deletions and duplications that may be found with CMA. These conditions, called microdeletion and microduplication syndromes, are often associated with intellectual disability and birth defects, but can vary significantly when it comes to severity.

See our Genetic Testing Results page to learn about the types of results that a chromosomal microarray can have.

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