FPGA ACCELERATION FOR DNA SEQUENCE ALIGNMENT

Abstract

In this paper, we present two new hardware architectures that implement the Smith–Waterman algorithm for DNA sequence alignment. Previous low-cost approaches based on Field Programmable Gate Array (FPGA) technology are reviewed in detail and then improved with the goal of increased performance at the same cost (i.e., area). This goal is achieved through low level optimizations aimed to adapt the systolic structure implementing the algorithm to the regular structure of FPGAs, essentially finding the optimum granularity of the systolic cells. The proposed architectures achieve processing rates close to 1 Gbps, clearly outperforming previous approaches. Comparing to the reported FPGA results of the computation of the edit-distance between two DNA sequences, throughput is doubled for the same clock frequency with a minimum area penalty. The design has been implemented on an FPGA-based prototyping board integrated into a bioinformatics system. This has allowed validating the approach in a real system (i.e., including I/O and database access), and comparing the proposed hardware solution to purely software approaches. As shown in the paper, the results are outstanding even for slow-rate buses.