Genotyping-by-sequencing (GBS) is a low-cost high throughput method for studying genetic variation, making it useful for genotyping and genetic mapping. Double digest GBS (ddGBS) uses two restriction enzymes to fragment the genome, followed by sequencing using next generation sequencing (NGS). It is particularly useful for large genomes and high-diversity species. Overall, GBS reduces genome complexity with restriction enzymes in an efficient, highly multiplexed sequencing approach to discover and genotype single nucleotide polymorphisms (SNPs) and has been widely used in crops and plants.