Brynn Levy, director of Columbia University's Clinical Cytogenetics laboratory and a clinical pathologist, is busy with a new multi-center grant to study how microarrays can diagnose prenatal diseases. GT's Ciara Curtin spoke with him about where cytogenetics and microarrays intersect. What follows are excerpts of their conversation, edited for space.
Genome Technology: You started out as a genetic counselor. Why did you move over to research?
Brynn Levy: I actually still [do clinical work] because I run the cytogenetics laboratory here at Columbia. But I have a very active research laboratory. I always wanted to be able to see a patient from all different aspects: be able to see the patient, counsel the patient, and know what goes on behind the diagnostics of it, in a really holistic way of seeing a patient from start to finish.
GT: How do you go about developing prenatal diagnostic tests? What sort of technology do you use?
BL: The prenatal tests that we are working on now are really part of the natural progression of what we call the molecular cytogenetics era. In the early '80s, cytogenetics began to utilize molecular techniques to be able to go beyond what we see visually on the chromosome and to go submicroscopically. The microarrays that we are using now are just the latest progression in the evolution of molecular cytogenetics. It enables us to get a very detailed examination of the chromosome, beyond what we can see microscopically. Most of it begins in an almost R&D environment in a research lab — typically starting off with some type of test or pilot study and developing it to a more sophisticated trial. I saw an opportunity with the oligonucleotide micro-arrays almost three years ago and partnered with Affymetrix, who weren't thinking of using it for cytogenetics, and decided to utilize their technology for copy number detection.
How do you start using this for prenatal? We're actually very fortunate that although microarrays are not a new concept, it is a fairly new concept in the last couple of years for clinical diagnostics. I'm very pleased that we're part of the multi-center trial which is an NIH-sponsored grant that will be utilizing microarrays for prenatal diagnosis. It involves us here at Columbia, Baylor, Emory, and Signature Genomics.
GT: What regulatory hurdles are there for these tests?
BL: Any clinical laboratory is subject to a variety of regulation before they can implement their clinical test, and this will be no different. [We'll need] clinical validations [and] approval by, at least for us here, the New York State Department of Health. We would have to show them all our validations and our protocols with how we go about utilizing this type of a test. It may be even a little bit more strict with the FDA getting interested in microarray type of diagnostics.
GT: Since the US can be so litigious, do you think physicians should worry if they do not run certain prenatal tests? Do you think there will be a rise of "wrongful birth" lawsuits?
BL: At least until the gold standard changes, I wouldn't see a basis for lawsuits. At the end of the day, that may be the negative aspect [of new technologies]. I never thought about that. The important thing is that for patients that are recommended prenatal testing for chromosome abnormalities, the types of abnormalities they are mostly at increased risk for are those that typically would still be able to be detected by routine methods. The most well-known one is Down's Syndrome. It does not take a sophisticated microarray to make a diagnosis of Down's Syndrome.