Hi Perumal, initial 65 C temperature is high enough for so called primer invasion. Of cause it is not as efficient as full denaturation but efficient enough. LAMP is much less efficient compare to PCR but it specifically used when you do not know sequence 3' of a known one. It is different types of gene fusions or, in generally, absence of a sequenced region.

Dear Dmitry Guschin,

 I think you are telling about RACE (Rapid amplification of cDNA ends), for amplification of unknown 3' ends. In LAMP as like PCR we most to know the 3' sequences to design primers.

Betaine which used in the LAMP reaction strongly decreased the melting temperature of the dna template wereby 60-65 degree Celsius is enough for partial denaturing of template.

Partial denaturation of dsDNA taking place in this temperature, then how oligo-primer will anneal in this temparature with use of betaine.

Thermodynamically it does not mean that 100% of the dna strands are separate from each other. In this experimental condition, some strands are still hybridized to each other. This rule holds true for primers.

Then how this test is more sensitive than PCR? Here it as to bind with four primers isothermal denatutation, primer binding, amplification and loop formation how is it possible? Do not compare with PCR melting, annealing and denaturation, because this is isothermal amplification, so every step need to take place at one thermal point.

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