454 Life Sciences, a Roche company, has launched the 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.
According to the company, they represent a major advance in speed and quality of characterisation of this 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 integrate the platforms into application-specific laboratory workflows.
The HLA genes encode for the immune system proteins that recognise foreign cells and other antigens.
Accurate characterisation 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.
Due to the highly polymorphic nature of this region of the human genome, the HLA genes present a challenge for genotyping.
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 long, clonal reads provided by 454 Sequencing Systems enable 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.
The GS Gtype HLA Primer Sets are the result of a multi-site study, published this month in the journal Tissue Antigens 1.
'We have sequenced thousands of samples and find the greater-than 99 per cent 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, study author and director of the HLA/Immunogenetics Laboratory at the Children's Hospital and 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,' she added.
