Loop Mediated Isothermal Amplification (LAMP) Test- a Novel Nucleic Acid Based Assay for Disease Diagnosis

Abstract

Disease diagnosis is of crucial importance in making appropriate therapeutic decisions. Conventionally, diagnosis was based on isolation and identification of the causative agent. This was followed in timeline by the development of serological tests. Nowadays, molecular tests credited with high sensitivity like polymerase chain reaction and its variants are replacing the older diagnostic techniques. Major obstacle in adoption of PCR based technique is the need for thermocycler, which precludes its use in low resource setting areas. Isothermal amplification system like Loop mediated isothermal amplification (LAMP) test is a good alternative. It is a novel nucleic acid amplification assay developed in 2000. Amplification of nucleic acid is carried out under isothermal condition, usually at temperature ranging from 60-65. Comparatively higher sensitivity, visual detection, lower reaction time, and dispensable use of thermocycler make LAMP an attractive option for field diagnosis. As the test is not susceptible to inhibitory effect of biological substances, it can be very well applied for direct detection from clinical samples without processing. Moreover, quantitaion of nucleic acid is possible by real time turbidity measurement. Till date, LAMP tests have been developed for diagnosis of a large number of diseases including bacterial, fungal, viral, and parasitic diseases. Instrument-free systems also have come up. In near future, microchip based LAMP system will be commercially available for point of care testing.