DNA profiling, also known as DNA typing, DNA fingerprinting, or DNA testing, allows the unequivocal identification of any living individual. This technique was developed in 1985 in forensic science to confound criminals, and was first applied to grape cultivars in 1993 by Australian researchers. Since a grape variety is made of clones reproduced asexually by vegetative propagation, it is genetically comparable to a human individual. The identification technique is based on small pieces of variable DNA called molecular markers, the most successful using repetitive pieces of DNA called microsatellites. They exist in any living organism and their length varies from one individual to another. Analysis of 8 to 12 microsatellites is enough to obtain a unique ‘genetic identity card’, looking like a supermarket bar code, for every variety. This technique, for which data exchanges between laboratories is relatively easy, allowed, for example, identification of the enigmatic petite sirah in California and solved the long-standing mystery of zinfandel’s identity.
