To elute DNA from agarose gel, the samples were loaded on a gel (1-1.8%) cast with low melting point agarose (LMP agarose ). The samples were resolved and visualized under UV transilluminator, and the band of interest was excised quickly using a scalpel blade. The volume of gel slice was quantitated by weighing and the DNA eluted using MinElute Gel Extraction kit (Qiagen) as per manufacturer's protocol. Briefly, the gel was solubilized by incubating it with buffer QG at 50°C for 10 min. The solubilized gel was loaded onto binding columns and centrifuged at 12,000 x g for 1 min. The flow-through was discarded and the column was washed once with buffer PE containing ethanol. The DNA bound to the column was eluted using the elution buffer provided with the kit, or alternatively with nuclease-free water. The concentration of the obtained DNA was estimated by measuring the absorbance at 260 nm (A26o) and using the following formula: DNA concentration= A260 X 50 X dilution factor.