Introducing htsget, a new GA4GH protocol for genomic data delivery

DNAnexus is here in Orlando for the fifth plenary meeting of the Global Alliance for Genomics and Health (GA4GH), the standards-making body advancing interoperability and data sharing for genomic medicine. We’re especially pleased this year to join in launching version 1.0 of htsget, a new protocol for the secure web delivery of large genomic datasets, especially whole-genome sequencing reads which can exceed 100 gigabytes per person. 

Htsget complements the incumbent BAM and CRAM file formats for reads, which GA4GH also stewards, and their ecosystem of tools. It adds a standardized protocol for accessing such data over the web, securely, reliably, efficiently, and even federally when needed. Retrieval with htsget is now built into the ubiquitous samtools via its underlying htslib library, allowing bioinformaticians to leverage htsget with most existing tools via a familiar Unix pipe. At the same time, htsget’s streaming parallelism enables scalable ETL into cluster environments like Apache Spark, providing a gradual transition path from incumbent file-based toolchains toward modern “big data” platforms. Lastly, htsget simplifies data access for interactive genome browsers, by unifying authentication and removing the need for index files.

On the server side, htsget has been deployed at the Sanger Institute and the European Genotype Archive; DNAnexus operates a multi-cloud htsget server indexing data within Amazon S3 and Azure Blob storage, which we call htsnexus; Google Cloud Platform has open-sourced their own implementation. Clients can speak a uniform protocol abstracting the diverse authentication and storage schemes of these service providers.

These groups, and others, have all shaped the htsget specification through the GA4GH’s highly collaborative process. But it started in large part with a contribution from DNAnexus, drawing on our experience optimizing how our systems utilize cloud object stores in the huge genome projects we’ve served, such as CHARGE, 1000 Genomes Project, TCGA, and HiSeq X Series data production. Through htsget and other work streams under the new GA4GH Connect framework announced today, DNAnexus looks forward to further contributing from our experience and network to advance the GA4GH’s essential mission.

For more information about how DNAnexus is working with htsget, please contact us at info@dnanexus.com.