Question

what is meant by non-coding regions in DNA and why are they important for DNA fingerprinting ?

Answer 1

Non-codind regions of DNA are the DNA that do not encode any proteins. They are also called Junk DNA. They are transcribed into functional non-coding RNA molecules (tRNA, rRNA, regulatory RNA) or a large proportion of them may have no biological function.

IMPORTANCE IN DNA FINGERPRINTING.

The non-coding regions of DNA are prone to changes in contrast to the coding DNA. Rightly so because if changes occur in essential coding DNA then it might not be able to work properly and the organism will be highly disadvantaged. Therefore, random variations come up in non-coding DNA. DNA fingerprinting takes advantage of these changes and creates a visible pattern of the differences to assess similarity. DNAs are cut at these points of differences. They are then digested or amplified using restriction digestion or PCR. The DNA fragments are separated and identified using agarose gel electrophoresis or sequencing. So the BANDS are generated. The number of bands and their sizes give a unique profile of the DNA from whence it derived. The more genetic similarity between a person, the more similar the banding patterns will be, and thus higher the probability that they are identical.