NEW YORK (GenomeWeb) – Agilent Technologies became the most recent company to enter the reproductive health market when it introduced its GenetiSure Pre-Screen Kit last month.
The company is marketing the comparative genomic hybridization microarray for screening aneuploidy and other genomic aberrations from single cells in three- and five day-embryos as part of the in vitro fertilization process.
Aneuploidy occurs when an embryo contains additional or missing chromosomes. The condition typically leads to termination of the developing fetus, or results in various diseases and disorders. Women typically turn to IVF clinics to reduce such risks, and new kits, both microarray and sequencing-based, provide clinicians with comprehensive information about the embryos prior to implantation.
Agilent’s kit contains a microarray slide containing eight arrays, each of which can accommodate two samples. Since each slide contains two controls, users can screen 14 samples on one chip. The firm claims its assay takes about eight hours to produce results.
While there are already many companies in the space, Agilent believes its offering’s relatively quick protocol and higher-throughput capacity will set it apart from competitors’ products.
"We see the IVF market as a growing opportunity with the increased need for genetic testing technologies in this space," said Nicole Ellis Ovadia, global senior product manager for molecular cytogenetics arrays at Agilent.
Ovadia told GenomeWeb that the new kit is "being marketed to labs that are screening single cells from embryos for aneuploidy using other array technologies and other customers who may be interested in innovating the processes in their lab."
She added that such customers should "experience a shorter turnaround time because of the shortened protocol allowing them to get results faster."
Turnaround time is an important factor in IVF clinics, where embryos are typically transferred between the third and fifth day following fertilization. According to Agilent, its arrays can detect aberrations in the 5- to 10-megabase range from single cells in three- and five-day embryos during this window of time. Agilent’s approach is based on a protocol designed by Ali Hellani, who is director of the Viafet Genomic Center in Dubai and genetics lab director at Fakih IVF, a fertility clinic also based in Dubai.
Hellani told GenomeWeb that he began offering 24-chromosome aneuploidy analysis using microarrays in 2008. At that time, the slides fit up to eight embryos and the protocol took more than 16 hours. Five years ago, he said he reduced the protocol time to 10 hours from 16 hours. "However, the test was still limited to eight embryos per slide," he noted.
Hellani was able to further reduce the turnaround time of his protocol in 2012, when Agilent began producing arrays that enabled the analysis of 14 arrays per slide, and he began to work to adapt his protocol to Agilent’s new arrays.
More specifically, the protocol consists of DNA amplification from a single cell, labeling of the amplified product, and hybridization on the array. Hellani said that Agilent's protocol differs from others in that it relies on Hellani's multiple displacement amplification technique, where the DNA obtained has an "enhanced quantity and quality when compared to others protocols." This improved DNA quality reduces the time necessary for hybridization, he said.
Hellani's method was then combined with Agilent's single-color labeling technique and 16-plex microarrays, which, according to Hellani improved the entire microarray protocol.
"By working together with Agilent over the past year, we were able to finalize the protocol into what is now that new Agilent GenetiSure 24-chromosome aneuploidy screening kit," said Hellani. "This protocol is the result of more than six years of experience in single-cell amplification and microarray analysis," he said. "The development of this protocol allows for a service that is cost effective with a short turnaround time, increasing the convenience for patients," he added.
According to Hellani, the commercialization of the arrays and the associated protocol should make applying microarrays for aneuploidy screening "very practical" for clinics and their patients. "As an example, Fakih IVF UAE, the clinic with the highest number of referred microarray cases, are sending the cells on Day 3 midday, and getting the result on Day 4 in the morning," said Hellani. "The new protocol allows for embryos to be transferred fresh on Day 4 or 5 and for the patients to receive their result after just one day."
One beta tester of the new kit was Richard Choy, director of the Pre-Implantation Genetic Diagnosis Center at the Chinese University of Hong Kong. Choy in a statement credited the arrays’ turnaround time, cost effectiveness, and resolution with his lab’s decision to use them.
"We are cautious about the overall cost and value of our screening," Choy said. "We are able to use the capacity of Agilent’s kit to address this price sensitivity, and it will be key technology in our work."
Choy did not respond to an email seeking comment.
There are plenty of firms out to capture a piece of the reproductive health market, among them Illumina, which serves the segment via its microarray-based 24sure pre-implantation screening kit, as well as its VeriSeq next-generation sequencing offering, which runs on its MiSeq system. Reproductive Health Science, Oxford Gene Technology, and CombiMatrix have all launched array-based PGS kits and services, while Bioarray and Good Start Genetics have either launched or intend to launch NGS-based PGS offerings.
According to Ovadia, Agilent’s array offers "several advantages over other offerings, including the less than eight-hour turnaround time, high-throughput capability with the ability to screen up to 14 samples plus two references per array, and a low price per sample."
She declined to elaborate on the price per sample for the new kit though, instead stating that Agilent’s offering is competitive with other technologies on the market.
Whatever its price, the kit is unique, even for Agilent, in its ability to assess 14 samples and two references on the same slide. It is the first 16-plex chip from the company and is manufactured at its headquarters in Santa Clara, Calif. using its inkjet fabrication method. Previously, Agilent’s highest multiplex arrays were in an eight-sample format.
And Ovadia hinted that the new kit may not be its last, either in the new 16-plex format or for IVF customers
"The clinical market is a major area of growth," said Ovadia. "Agilent will continue to be in close dialogue with our customers about how best to address their needs by focusing on development and introduction of new products in this space."