Presentation on theme: "KEY CONCEPT DNA fingerprints identify people at the molecular level."— Presentation transcript:
1 KEY CONCEPT DNA fingerprints identify people at the molecular level.
2 REVIEW from 9.1Gel electrophoresis is used to separate DNA fragments by size.A DNA sample is cut with restriction enzymes.Electrical current pulls DNA fragments through a gel.
3 A DNA fingerprint is a type of restriction map. DNA fingerprints are based on parts of an individual’s DNA that can be used for identification.based on noncoding regions of DNA that have repeating DNA sequencesnumber of repeats differs between people
4 A DNA fingerprint is NOT actually a fingerprint! XXA DNA fingerprint is NOT actually a fingerprint!
5 DNA fingerprinting is used for identification. DNA fingerprinting depends on the probability of a match.Many people have the same number of repeats in a certain region of DNA.The probability that two people share identical numbers of repeats in several locations is very small.(mother) (child 1) (child 2) (father)
7 Several regions of DNA are used to make DNA fingerprints. Individual probabilities are multiplied to find the overall probability of two DNA fingerprints randomly matching.,400,0001 chance in 5.4 million people to have the same DNA fingerprintx=1 in every 500 people has 3 copies in location A1 in every 90 people has 6 copies in location B1 in every 120 people has 10 copies in location cSeveral regions of DNA are used to make DNA fingerprints.
8 DNA fingerprinting is used in several ways. evidence in criminal casespaternity tests(Who da’ Daddy???)immigration requestsstudying biodiversitytracking genetically modified crops
9 CC GG Who Ate the Cheese? Get into pairs Each pair needs a Bio book Read the Royal Incident ReportThe restriction enzyme used will always cut between CCGGCreate you DNA Fingerprint restriction mapCC GGObjective: You will examine crime evidence and model the process of gel electrophoresis and DNA fingerprinting to identify the person who ate the Queen’s cheese.