The invention includes methods for aligning reads (e.g., nucleic acid reads, amino acid reads) to a reference sequence construct, methods for building the reference sequence construct, and systems that use the alignment methods and constructs to produce sequences. The method is scalable, and can be used to align millions of reads to a construct thousands of bases or amino acids long. The invention additionally includes methods for identifying a disease or a genotype based upon alignment of nucleic acid reads to a location in the construct.