What is the specific computational advantage of using the Burrows-Wheeler Transform (BWT) combined with an FM-index compared to a standard hash-table alignment method when mapping short reads to a reference genome?

The primary computational advantage of using the Burrows-Wheeler Transform combined with an FM-index is the dramatic reduction in memory usage compared to hash-table methods, which allows for mapping sequences to large genomes on standard consumer hardware. A hash-table index requires storing the reference genome plus additional data structures to map every k-mer, which are fixed-length substrings of the genome, to the....