Thespatyping method is based on sequencing of the polymorphic X region of the protein A gene (spa), present in all strains ofStaphylococcus aureus.The X region is constituted of a variable number of 24-bp repeats flanked by well-conserved regions. This single-locus sequence-based typing method combines a number of technical advantages, such as rapidity, reproducibility, and portability. Moreover, due to its repeat structure, thespalocus simultaneously indexes micro- and macrovariations, enabling the use ofspatyping in both local and global epidemiological studies. These studies are facilitated by the establishment of standardizedspatype nomenclature and Internet shared databases.
