454 Life Sciences, a Roche Company, announced the launch and immediate availability of the new GS GType HLA primer sets for high- and medium-resolution genotyping of class I and class II loci of the Human Leukocyte Antigen (HLA) genes. The primer sets are designed for use with the company’s benchtop GS Junior and GS FLX next-generation sequencing systems – enabling high-resolution typing and unambiguous allele assignment in a single run.

The solution represents a major advance in speed and quality of characterization of this immunologically important and highly variable region of the human genome. The kits are the first in a series of research assays in the areas of immunogenetics, infectious disease, and cancer to be launched for use with 454 Sequencing Systems, allowing researchers to easily integrate the platforms into application-specific laboratory work flows.

The HLA genes encode for the immune system proteins that recognize foreign cells and other antigens. Accurate characterization of an individual’s HLA type is important for research in tissue transplantation matching, while variations in these genes have known association with a wide variety of autoimmune diseases, infectious diseases, and some cancers.

The HLA genes present a challenge for genotyping due to the highly polymorphic nature of this region of the human genome. Traditional sequence-based typing using Sanger capillary electrophoresis technology is unable to resolve ambiguities and set phase without requiring multiple iterations, interspersed with significant manual analysis of the data, and often the use of multiple technologies.

The unique long, clonal reads provided by 454 Sequencing Systems enable straightforward high-resolution HLA typing of multiple samples at a time and, in many cases, achieve unambiguous allele identification within a single sequencing run.  Sequence output is compatible with third party HLA genotyping software tools – offering researchers a complete solution from DNA to genotype assignment.

The GS GType HLA Primer Sets are the result of an extensive multi-site study, published this month in the journal Tissue Antigens 1. “We have sequenced thousands of samples and find the  >99% concordance rate, increased throughput and significant reduction of ambiguity is far superior using the Roche GS FLX System over Sanger-based approaches,” said Elizabeth Trachtenberg, PhD, study author and director of the HLA/Immunogenetics Laboratory at the Children’s Hospital & Research Center Oakland. “Using this approach, we can obtain a high-resolution allele assignment in approximately one-third the time necessary using Sanger-based methods.”

“454 Sequencing Systems offer a major advance for high-resolution, high-throughput HLA typing,” explained Henry Erlich, PhD, senior study author and director of the Department of Human Genetics at Roche Molecular Systems. “The ability to quickly achieve such high accuracy and resolution will have a significant impact on research and, ultimately, on clinical application of HLA typing.”

Roche is a leader in research-focused healthcare with combined strengths in pharmaceuticals and diagnostics and with truly differentiated medicines in oncology, virology, inflammation, metabolism and CNS.