Chromosomal Microarray Promoted as Standard of Care for Prenatal Diagnosis


Traditionally in high risk pregnancies, a Fluourescent In-Situ Hybridization (FISH) karyotype is performed on samples from the placenta or amniotic fluid to screen for prenatal diseases. This past Wednesday, two studies published in the New England Journal of Medicine, found that chromosomal microarrays, a lesser known form of genetic testing, are just as and often more effective than FISH karyotyping when testing for prenatal genetic abnormalities.  The first study found that chromosomal microarrays were able to identify additional and significant cytogenetic information above FISH.  These microarrays were also equally successful in identifying aneuploidies (extra or missing copies of chromosomes) as well as unbalanced chromosomal rearrangements.  According to Ronald J. Wapner, the lead researcher for the New England Journal of Medicine study ,“The biggest advantage of microarray is it can give us a lot more information.”

The second study used chromosomal microarray technology to analyze 532 stillbirths. The microarrays were able to determine the cause of stillbirth in 87 percent of cases, compared to 71 percent using conventional testing methods (FISH). Unlike conventional testing, microarrays are able to determine whether prenatal heart defects are caused by genetics.  The broadening access to chromosomal microarrays for high-risk pregnancies will provide prospective parents with more information about the health of their future child and allow them to make well informed decisions.


About Author

Stephany Foster

Stephany Foster is the Associate Scientific Writer at Recombine, a genetic testing company based in New York City. She writes on topics spanning fertility, reproductive medicine, and recent advances in genomics. Stephany also writes about recently published research that Recombine presents at conferences and meetings around the globe. Before joining Recombine, Stephany interned at the George Church Lab at Harvard Medical School. She graduated from Brown University with an A.B. in Biology in 2014.

  • “5. Don’t trust diagnoses of cidoitonns”–I think “5” is a big one, particularly when it comes to things like ADHD, schizophrenia and autism. There is a tendency to lump etiologically distinct disorders under the same umbrella of diagnosis.Variable etiology is also a likely confound of studies looking for height genes. You can be tall because you produce more growth hormone than average (the theory of Polynesians as hypertrophied Asians), or you can be tall because the growth plates in your long bones are more sensitive to growth hormone than average, or because you simply grow for a longer period of time than average, or because you are simply healthier and better fed than average. So a study looking for height genes would have its work cut out for it, sifting through all these associations. I have no doubt that genes for height exist, (one needs only to look at the families around them to see evidence for the heritability of body size) but finding those genes will be hard.