Question

DNA finger printing involves

• A. Agglutinations
• B. Chromatography
• C. Electrophoresis
• D. Both (B) and (C)

Answer 1

Answer: (C)

Electrophoresis

DNA fingerprinting refers to the use of techniques like polymerase chain reaction (PCR) to reveal the specific DNA profile for a particular organism which is as unique as a fingerprint. A DNA fingerprint is generally independent of environment and is consistent throughout different parts and developmental stages of the organism. The similarity of DNA fingerprints depends on the genetic closeness of tested samples. As most proteins are not directly visible on gels to the naked eye, a method has to be employed in order to visualize them following electrophoresis. The most commonly used protein stain is the dye Coomassie brilliant blue. After electrophoresis, the gel containing the separated proteins is immersed in an acidic alcoholic solution of the dye. This denatures the proteins, fixes them in the gel so that they do not wash out, and allows the dye to bind to them. After washing away excess dye, the proteins are visible as discrete blue bands. Chromatographic techniques such as high-performance thin-layer chromatography and high-performance liquid chromatography provide chemical fingerprinting or the profiling of various chemical constituents of species. Chromatography is a method used by scientists for separating organic and inorganic compounds so that they can be analyzed and studied. By analyzing a compound, a scientist can figure out what makes up that compound. Chromatography is a physical method for observing mixtures and solvents.