Sequenom last week became the first major player in the next-generation sequencing-based, non-invasive prenatal testing market to offer chromosomal microarray analysis services to its customers.
It is not clear if other NIPT providers, such as Verinata Health and Ariosa Diagnostics will follow suit, but at least one other company that offers NIPT, Natera, said that it has no immediate plans to provide a similar CMA service to its customers.
San Diego-based Sequenom's new offering is being made possible through an agreement with Irvine, Calif.-based CombiMatrix, a clinical laboratory that specializes in CMA and has offered array-based testing for seven years. The firm uses an Agilent Technologies-manufactured comparative genomic hybridization array in its services.
Sequenom's MaterniT21 PLUS test analyzes the relative amount of 21, 18, 13, as well as X and Y chromosomal material in cell-free DNA. The test is intended for use in pregnant women at increased risk for fetal aneuploidy and can be used as early as 10 weeks' gestation.
According to a statement, Sequenom and CombiMatrix will offer CMA to customers to "broaden and confirm" the results of the MaterniT21 PLUS test. The two companies said they also plan to provide, when clinically appropriate, a comprehensive test result report for ordering physicians.
Under the terms of the deal, the Sequenom Center for Molecular Medicine will work with CombiMatrix to promote both services, as well as to provide technical training to physicians and counseling, and education and support services to physicians and their patients.
Marcy Graham, senior director of investor relations at Sequenom, told BioArray News this week that the firm suggests that doctors confirm any positive findings from MaterniT21 PLUS with an invasive procedure.
While extracted amniotic fluid has been analyzed by fluorescence in situ hybridization or conventional karyotyping, the availability of microarray technology "fit well with our next-gen sequencing approach."
Graham noted that chromosomal microarray analysis is "considered by many to provide improved resolution and accuracy over traditional karyotyping." She cited the results of a US National Institute of Child Health and Human Development-funded study that demonstrated that arrays provide more clinically relevant information than older methods and suggested that CMA replace karyotyping as a first-tier test. A paper detailing the study appeared in the New England Journal of Medicine last year (BAN 12/11/2012).
"We wanted to make sure we selected the most accurate invasive technology to complement our MaterniT21 PLUS test results," Graham said of the CombiMatrix deal. "We believe our customers will appreciate the single-solution prenatal testing value we can now provide."
CombiMatrix CEO Mark McDonough in a statement called the new arrangement with Sequenom a "significant validation of the rapidly expanding acceptance of CMA as a standard of prenatal care."
McDonough in the past has portrayed the development of the NIPT market as expanding opportunities for the increased adoption of CMA.
"It is important to keep in mind that those tests screen for specific conditions such as Down syndrome, and that the vast majority of these [noninvasive] tests come back negative," McDonough said in March (BAN 3/5/2013). "Many of the parents facing this uncertainty will want the broader information provided by a microarray."
Not all providers of NIPT plan to make CMA directly available to their customers though.
Solomon Moskevich, head of business development at Natera, said that the company has not partnered with any other labs to provide CMA testing to accompany its sequencing-based Panorama Test.
At the same time, Moskevich said that the San Carlos, Calif.-based company has "deep experience" providing SNP microarray analysis of embryonic cells during in vitro fertilization, products of conception samples, and prenatal paternity testing using fetal cell-free DNA from maternal blood.
"If we believed that prenatal CMA testing was a valuable service to offer our clients, we would do it by ourselves using a SNP array instead of partnering with another lab," Moskevich told BioArray News.
He added that he believes SNP arrays, as opposed to comparative genomic hybridization arrays, support a "much better analytical approach than quantitative CMA, because it allows the detection of triploidy and uniparental disomy."
Natera launched the Panorama Test in December 2012. The test identifies aneuploidies of chromosomes 21, 18, 13, X and Y.
Another NIPT player that could potentially offer a single NIPT and CMA service could be Verinata Health. Illumina acquired Verinata earlier this year, just months after it bought Cambridge, UK-based BlueGnome, a provider of microarrays and software for constitutional and cancer cytogenetics.
While Illumina executives have touted the complementarity of Verinata's non-invasive Verifi Test with BlueGnome's menu of arrays, they have not yet rolled out such a direct offering to customers. Greg Heath, senior vice president and general manager of Illumina's Diagnostics business, told BioArray News in June that the firm does see its BlueGnome and Verinata businesses as existing "along the continuum of reproductive health," meaning that Illumina's NIPT customers could move on to array-based testing, if desired (BAN 6/18/2013).
Representatives of Illumina and Ariosa, another NIPT player, did not respond to questions in time for this publication.