New software analyses human genomes faster than others

Investigators at Nationwide Children’s Hospital have developed an analysis “pipeline” that slashes the time it takes to search a person’s genome for disease-causing variations from weeks to hours.

“It took around 13 years and $3 billion to sequence the first human genome,” says Peter White, PhD, principal investigator and director of the Biomedical Genomics Core at Nationwide Children’s and the study’s senior author. “Now, even the smallest research groups can complete genomic sequencing in a matter of days. However, once you’ve generated all that data, that’s the point where many groups hit a wall. After a genome is sequenced, scientists are left with billions of data points to analyse before any truly useful information can be gleaned for use in research and clinical settings.”

To overcome the challenges of analysing that large amount of data, Dr. White and his team developed a computational pipeline called “Churchill.” By using novel computational techniques, Churchill allows efficient analysis of a whole genome sample in as little as 90 minutes.

“Churchill fully automates the analytical process required to take raw sequence data through a series of complex and computationally intensive processes, ultimately producing a list of genetic variants ready for clinical interpretation and tertiary analysis,” Dr. White explains. “Each step in the process was optimized to significantly reduce analysis time, without sacrificing data integrity, resulting in an analysis method that is 100 percent reproducible.”

The output of Churchill was validated using National Institute of Standards and Technology (NIST) benchmarks. In comparison with other computational pipelines, Churchill was shown to have the highest sensitivity at 99.7 percent; highest accuracy at 99.99 percent and the highest overall diagnostic effectiveness at 99.66 percent.

“At Nationwide Children’s we have a strategic goal to introduce genomic medicine into multiple domains of paediatric research and healthcare. Rapid diagnosis of monogenic disease can be critical in new-borns, so our initial focus was to create an analysis pipeline that was extremely fast, but didn’t sacrifice clinical diagnostic standards of reproducibility and accuracy” says Dr. White. “Having achieved that, we discovered that a secondary benefit of Churchill was that it could be adapted for population scale genomic analysis.”

By examining the computational resource use during the data analysis process, Dr. White’s team was able to demonstrate that Churchill was both highly efficient (>90 percent resource utilization) and scaled very effectively across many servers. Alternative approaches limit analysis to a single server and have resource utilization as low as 30 percent. This efficiency and capability to scale enables population-scale genomic analysis to be performed. Nationwide Children’s Hospital