Illumina Introduces Sentrix(R) HumanHap650Y Genotyping BeadChip; Product Sets New Standard for SNP Density and Genomic Coverage on a Single Array; HIV among First Areas to Be Studied.

SAN DIEGO -- Illumina, Inc. (NASDAQ:ILMN) announced today that it has introduced a new Sentrix(R) HumanHap Genotyping BeadChip that extends broad genomic coverage to all four populations studied by the International HapMap Project including the Yoruba in Ibadan, Nigeria. The Yoruba (see Note) show greater genetic diversity than European and Asian people who experienced population bottlenecks in relatively recent human history. This diversity demands a significantly higher number of SNPs (single nucleotide polymorphisms) than less-diverse, younger populations to achieve equivalent genomic coverage.

Illumina's HumanHap650Y BeadChip contains over 650,000 SNP markers on a single microarray, providing the most comprehensive genomic coverage and highest data quality of any whole-genome genotyping product currently available. Illumina expects to begin shipping the HumanHap650Y in July.

By genotyping DNA samples with the new HumanHap BeadChips, researchers will be better equipped to compare genetic variation between different populations, comprehensively identify SNP loci of interest, and then track and validate disease-related genetic variations. Scientific teams are already designing large studies around the new HumanHap BeadChip.

One such study will be conducted at Duke University's Center for HIV/AIDS Vaccine Immunology (CHAVI). As part of the study, CHAVI will use the HumanHap650Y to analyze a 2,000-sample cohort of HIV-exposed African individuals that are and are not infected with the virus in order to identify gene variants that confer either resistance or susceptibility to infection.

According to David Goldstein, Ph.D., a Professor in Duke's Institute for Genome Sciences & Policy and Director of CHAVI's Host Genetics Core, "The CHAVI host genetics group was delighted by the announcement of this product which represents a dramatic step forward for whole genome association studies in Africa."

"The introduction of the Hap650Y highlights the quality of our product development process, the robustness of our manufacturing infrastructure and the flexibility of BeadArray(TM) technology," stated Jay Flatley, Illumina President and CEO. "In the three short months since we launched our flagship HumanHap550, we have screened and validated over 100,000 Yoruba tagSNP assays, developed multiplexed bead pools, and conducted final product QC for a brand new human genotyping BeadChip."

HumanHap BeadChips are powered by Illumina's revolutionary Infinium(TM) assay method (see Note), which enables the Company to select virtually any SNP, including so called "tagSNPs," to deliver the highest per-marker information content. TagSNPs deliver high information value because they often serve as "proxies" for larger groups of SNPs, called haplotypes, which are inherited together. SNP selection for the Hap650Y was developed collaboratively with an advisory board that was also used to aid in content selection for the entire predecessor family of HumanHap BeadChips including the Hap300, the Hap240S, and the Hap550.

The Sentrix HumanHap650Y BeadChip is the latest addition to Illumina's growing genotyping portfolio that includes whole-genome arrays, focused-content arrays and SNP linkage panels, and powerful assay protocols such as the GoldenGate(R) and Infinium assays. Illumina also works with customers to install robust infrastructure solutions, including automation and LIMS (laboratory information management systems) for large-scale sample throughput, positive sample tracking, and data analysis and management.

More Information

For more information about the new HumanHap650Y BeadChips and related Infinium reagent kits or about other high-performance microarray products for genotyping and gene expression studies, contact Illumina's Customer Solutions Department at [phone] or e-mail [e-mail].

About Illumina

Illumina (www.illumina.com) develops and markets next-generation tools for the large-scale analysis of genetic variation and function. The Company's proprietary BeadArray technology -- used in leading genomics centers around the world -- provides the throughput, cost effectiveness and flexibility necessary to enable researchers in the life sciences and pharmaceutical industries to perform the billions of tests necessary to extract medically valuable information from advances in genomics and proteomics. This information will help pave the way to personalized medicine by correlating genetic variation and gene function with particular disease states, enhancing drug discovery, allowing diseases to be detected earlier and more specifically, and permitting better choices of drugs for individual patients.

Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995: this release may contain forward-looking statements that involve risks and uncertainties. Among the important factors that could cause actual results to differ materially from those in any forward-looking statements are the costs and outcome of Illumina's litigation with Affymetrix, the Company's ability to scale and integrate CyVera technology, the ability to further scale oligo synthesis output and technology to satisfy market demand deriving from the Company's collaboration with Invitrogen, Illumina's ability to further develop and commercialize its BeadArray technologies and to deploy new gene expression and genotyping products and applications for its platform technology, to manufacture robust Sentrix(R) arrays - including HumanHap BeadChips -- and Oligator(R) oligonucleotides, and other factors detailed in the Company's filings with the Securities and Exchange Commission including its recent filings on Forms 10-K and 10-Q or in information disclosed in public conference calls, the date and time of which are released beforehand. Illumina disclaims any intent or obligation to update these forward-looking statements beyond the date of this release.

Editors' Notes

Importance of the Yoruba Population

The fossil record and genetic evidence indicate that all humans today are descended from anatomically modern ancestors who lived in Africa about 150,000 years ago. The International HapMap Project (www.hapmap.org) studied the genetic diversity of individuals from four populations of modern humans and found, as expected, that the Yoruba of Ibadan, Nigeria have greater genetic diversity than people of northern European descent, Han Chinese from Beijing, or Japanese from Tokyo. Most of the variation of current human populations comes from the ancestral population, but more recent populations grew from restricted numbers of individuals who carried only part of human diversity. The Yoruba people are thought to carry a more complete representation of human diversity. The HumanHap650Y is projected to cover 70% of common Yoruba genetic diversity, and more than 90% of the common diversity of the other HapMap populations at r squared = 0.8.

Infinium Assay Note

The Infinium Assay is notable for its simplicity, its high locus specificity and allelic discrimination, and its ability to interrogate a broad range of SNPs with little constraint on locus selection. This, in turn, enables scalability limited only by the number of features on the array itself (the HumanHap650 BeadChip contains over 12 million features). Following single-tube, whole-genome amplification (no PCR or ligation steps), samples are hybridized to 50-mer bead-based probes. After a labeled extension step, the BeadChip is imaged on Illumina's BeadArray Reader, and then analyzed. Call rates routinely exceed 99%, with reproducibility and accuracy approaching 100% and HapMap concordance above 99.7%.

Additional Assay Reference

"Whole-Genome Genotyping with the Single-Base Extension Assay," Frank J. Steemers, Weihua Chang, Grace Lee, David Barker, Richard Shen and Kevin Gunderson, Nature Methods, Vol. 3, No. 1, January 2006.