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AS/A-Level Chemistry - DNA fingerprinting

DNA fingerprinting

August 1, 2021

Let's learn how DNA fingerprinting works and how it is used in A-Level Chemistry!

DNA fingerprinting is used to determine the probability that genetic material came from a particular individual. 

It is used for:  Solving crimes, clarifying immigration disputes and to establish paternity or maternity

How does it work?

• A DNA sample is obtained and it cut into fragments using a restriction enzyme 

• The resulting solution is applied to a gel

• The DNA fragments are subjected to an electrical field

• The DNA fragments are electrically charged owing to the negative charges carried by the phosphate groups and so the different-sized DNA fragments move at different speeds through the gel towards the positive electrode

• This process is known as electrophoresis 

• Each fragment is marked by a probe and exposed on X-ray film

• This produces a pattern of black bars

Ownership

• Who should have access to personal genetic information?

• Who owns and controls genetic information?

• Who owns genes and other pieces of DNA?

DNA Testing

• Should parents have the right to have their children tested?

• Should tests be performed for genetic diseases?

• Should an individual always be given his/her genetic information?

Drafted by Eunice (Chemistry)

References:

https://www.biotechniques.com/pcr-sequencing/putting-dna-fingerprinting-behind-bars/

https://www.nejm.org/doi/pdf/10.1056/NEJM199502233320812