This post now includes the news that beginning this month Counsyl will require a physician's order to perform its carrier-screening assay.

By Kirell Lakhman

It's been a busy few days for tracking the changing fortunes of next-gen sequencers in molecular diagnostics. First Sequenom said it will run its Downs assay on an NGS; then Helicos said it shed half its staff and may shut down if it can't find fresh cash; and now Ambry Genetics is considering moving on from its two Illumina GAs.

And last week a new report found that lab directors expect next-gen sequencers to replace around 16 percent of microarray usage in their labs by 2011, and supplant up to one-third within three years.

Ambry later this summer will begin offering a prenatal carrier-screening test that runs on Illumina Genome Analyzer sequencer, though the company is considering alternative next-generation platforms.

The assay, called AmbryScreen, is expected to make its debut over the next four to six weeks as Ambry finishes validating it, the company said yesterday.

With a price tag of $450, the homebrew test will screen for several hundred well-understood disease-causing mutations linked to more than 90 severe or common genetic diseases with pediatric onset.

AmbryScreen will compete with a Silicon Valley start-up that has been selling a similar test directly to consumers since January. However, beginning this month the company, called Counsyl, will require a doctor to order the test and will send the results directly to the physician for interpretation. The microarray-based test screens for more than 100 diseases and costs around $350.

Ambry's disclosure that it is considering alternative sequencing platforms is the latest in a newsworthy few weeks for tracking the evolution of next-gen sequencers in the clinical lab.

Today, Helicos BioSciences said it has shed half its staff in a bid to cut costs; that it plans to reposition its HeliScope platform for diagnostic applications; and that it may be forced to close its doors if it can't raise fresh capital.

And two weeks ago Sequenom said it will develop its much-delayed trisomy 21 Down syndrome test solely on a next-gen sequencer, and that it has narrowed its choice to Illumina's GA II and HiSeq 2000 platforms, and ABI's SOLiD instrument.

And all of this was capped last week by a report from JP Morgan's Life Science Tools & Diagnostics group that found that, on average, 16 percent of surveyed lab directors expect next-gen sequencers to replace around 16 percent of microarray usage in their labs by 2011, and supplant up to one-third within three years.