This article was originally posted on Nov. 20.
23andMe said last month that it will soon begin genotyping its customers on a new, custom-designed, higher-throughput microarray.
As it discussed in a Nov. 18 blog post, 23andMe had previously offered its consumer genomics using catalog Illumina chips containing some custom content.
Spokesperson Catherine Afarian confirmed to BioArray News that the company will soon move to a "100 percent custom chip design" that contains more than 500,000 markers and that is hand-curated by 23andMe scientists. She said that the chip's design and format offer several advantages for the Mountain View, Calif.-based company.
In terms of content, Afarian noted that for the first time since it launched its services six years ago, 23andMe selected all of the markers on the chip. This allowed the company to eliminate SNPs from previous chip designs that were not informative to its reports or research, she said. It has also enabled the firm to "maximize the number of actionable health reports we can provide to our customers," as well as to provide more detailed ancestry analyses.
In the blog post, the company noted that the custom chip contains markers that will also allow its researchers to better impute many variants present on larger arrays.
In October, Illumina introduced a new 24-sample format for its Infinium BeadChips, doubling the throughput of its previous highest-throughput offerings. Afarian confirmed that 23andMe's new array is being manufactured in Illumina's new 24-sample format.
"Changing formats enables us to be more efficient," said Afarian. She noted that the company had previously been using a version of Illumina's HumanOmniExpress that contained some custom markers and that allowed it to process eight samples per chip. The move to the new, higher-throughput format "significantly increases our lab capacity and will help increase the turnaround time of results to customers," Afarian said.
She noted that the new chip is "backwards compatible," meaning that there will be no significant difference in the reports provided to customers who were tested using its previous array. The company told customers in its blog post that there would be "little reason" to retest on the latest platform. It did acknowledge that there may be smaller differences in the reports it issues to its clients, and said that it would inform its customers of those differences in community posts.
Afarian declined to provide additional information on the new chip design, stating that the firm does not discuss content curation and that its development processes are proprietary.
The company's new chip is the fourth it has used since its 2007 launch. Other players in the consumer genomics space, such as Ancestry.com and Family Tree DNA, continue to rely on Illumina's OmniExpress, while National Geographic's Genographic Project has used a custom, 130,000-marker Illumina HD iSelect BeadChip since it rolled out the second, array-powered phase of the project, called Geno 2.0, last year. Genographic Project Director Spencer Wells told BioArray News in August, though, that the project was in the process of designing a new array that would succeed its current chip.