The article describes a novel approach to rapid SNP discovery and genetic mapping using sequenced RAD (restriction-site associated DNA) markers. The authors developed a method for generating and sequencing RAD tags, which allowed the identification of over 13,000 SNPs and the mapping of three traits in two model organisms. They demonstrated that different marker densities can be achieved by choosing different restriction enzymes and that barcoding systems can facilitate sample multiplexing and fine mapping. The approach was validated by mapping lateral plate armor loss in threespine stickleback and a reduction in pelvic structure, as well as an induced mutation in Neurospora crassa. The study highlights the versatility and efficiency of sequenced RAD markers for genetic mapping in various organisms, offering a cost-effective and high-throughput platform for SNP discovery and genotyping.The article describes a novel approach to rapid SNP discovery and genetic mapping using sequenced RAD (restriction-site associated DNA) markers. The authors developed a method for generating and sequencing RAD tags, which allowed the identification of over 13,000 SNPs and the mapping of three traits in two model organisms. They demonstrated that different marker densities can be achieved by choosing different restriction enzymes and that barcoding systems can facilitate sample multiplexing and fine mapping. The approach was validated by mapping lateral plate armor loss in threespine stickleback and a reduction in pelvic structure, as well as an induced mutation in Neurospora crassa. The study highlights the versatility and efficiency of sequenced RAD markers for genetic mapping in various organisms, offering a cost-effective and high-throughput platform for SNP discovery and genotyping.