Description
In this dissertation, we describe the ADAM system for processing large genomic datasets using distributed computing. ADAM provides a decoupled stack-based architecture that can accommodate many data formats, deployment models, and data access patterns. Additionally, ADAM defines schemas that describe common genomic datatypes. ADAM’s schemas and programming models enable the easy integration of disparate genomic datatypes and datasets into a single analysis.
To validate the ADAM architecture, we implemented an end-to-end variant calling pipeline using ADAM’s APIs. To perform parallel alignment, we developed the Cannoli tool, which uses ADAM’s APIs to automatically parallelize single node aligners. We then implemented GATK-style alignment refinement as part of ADAM. Finally, we implemented a biallelic genotyping model, and novel reassembly algorithms in the Avocado variant caller. This pipeline provides state-of-the-art SNV calling accuracy, along with high (97%) INDEL calling accuracy. To further validate this pipeline, we reanalyzed 270 samples from the Simons Genome Diversity Dataset.