SCAR markers: a potential tool for authentication of herbal drugs

Randomly Amplified Polymorphic DNA (RAPD) is easy to develop and simple molecular marker, but lack of reproducibility makes it less reliable for authentication of herbal drugs. Besides RAPD, other popular PCR and non-PCR based markers like AFLP, ISSR, SSR and RFLP are also used for authentication. However, these also have disadvantages like use of radioactive isotopes, high cost and absolute requirement of sequence information. Therefore, it is a better option to improve the reproducibility of RAPD by converting RAPD amplicons into Sequence Characterized Amplified Region (SCAR) markers. SCAR markers are easy, reliable and reproducible thus, have an advantage over RAPD markers for authentication of medicinal herbs used in the preparation of traditional medicines. These markers however, have been developed for only a few medicinal herbs. This review is an attempt to evaluate critically the role of SCAR markers in authentication of medicinal herbs used in traditional formulations.