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DNA FINGERPRINTING. Instructor Terry Wiseth. NEXT SLIDE. Marker Board
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DNA FINGERPRINTING InstructorTerry Wiseth NEXT SLIDE
MarkerBoard DNA. It's what makes you unique. It's the stuff that tells each and every one of your body's 10 trillion cells what it's supposed to be and what it's supposed to do. And although your DNA is different from that of every other person in the world -- unless you have an identical twin -- it's the same in every cell that makes up your body. There are three exercises to perform for this lab. Click on the exercise listed below that you will be performing. Click on the marker board on the right side to view information and instructions on the DNA lab GEL ELECTROPHORESIS PATERNITY TESTING DNA FINGERPRINTING ENDLAB
There are three exercises to perform for this lab. Click on the exercise listed below that you will be performing. GEL ELECTROPHORESIS PATERNITY TESTING DNA FINGERPRINTING END LAB ENDLAB
DNA FINGERPRINTINGDNA. It's what makes you unique. It's the stuff that tells each and every one of your body's 10 trillion cells what it's supposed to be and what it's supposed to do. And although your DNA is different from that of every other person in the world -- unless you have an identical twin -- it's the same in every cell that makes up your body. NEXT SLIDE
That DNA is unique from person to person but the same from cell to cell in one person can be a handy thing, especially when it comes to DNA fingerprinting. DNA fingerprints can be used for anything from determining a biological mother or father to identifying the suspect of a crime. And, as may someday be used to clear someone's name. NEXT SLIDE
But what exactly is a DNA fingerprint? Well, it certainly isn't an inky impression of a DNA strand. Compared to unimaginably small DNA, a fingerprint is HUGE. So what is it that we're looking at, and how is one of these fingerprints made? NEXT SLIDE
Here's your chance to find out. You'll find out by solving a mystery -- a crime of sorts. Solving the mystery involves creating a DNA fingerprint (we'll supply the lab and all necessary materials) and comparing this fingerprint to those of the suspects. NEXT SLIDE
Your task, as NORTHLAND Lab's chief technician, is to create a DNA fingerprint from the saliva left on a lollipop. You must then use the fingerprint to single out the culprit of this crime. Are you ready? Then get to work! Go to the next slide to get started. Remember you will need toanswer thequestions 1-5when you arefinished. NEXT SLIDE
Part 1: It Takes a Lickin'...The Crime On the evening of November 1, at approximately 8:15 p.m., Jimmy Sweet entered his bedroom, walked over to his desk, and sat down at his computer. While reaching for the computer's switch he noticed, out of the corner of his eye, that one of the items on a typically well-organized shelf was out of place. NEXT SLIDE
Jimmy shot across the room for a closer examination. Sure enough, the object in question had indeed been disturbed. The object had been sealed in an air-tight package. The package was now ripped open. The object was still inside, but it was no longer in its original condition. In Jimmy's eyes, it was now worthless. NEXT SLIDE
Jimmy pulled out what had been his most-valued possession -- his holographic NOVA lollipop. The confectionery treat was now a sticky mess. Someone had obviously indulged him- or herself in its sugary molecules. The lollipop's holographic image had been licked away. NEXT SLIDE
The SuspectsThe prime suspects in this case are Jimmy's seven sisters: Candy, Cookie, Sugar, Lolly, Honey, Brandee, and Carmela. Each one of these sisters is a notorious candy lover and is easily capable of committing this crime of confection.The suspects have been detained. DNA fingerprints of each are available. NEXT SLIDE
What You Need to Do Fortunately for this case, a lollipop cannot be licked without leaving behind a bit of saliva. Your task, as NORTHLAND Lab's chief technician, is to create a DNA fingerprint from the saliva left on the lollipop. You must then use the fingerprint to single out the culprit of this crime. NEXT SLIDE
Click on the link titled"It Takes a Lickin'...“below to get started.You will be required to be connected to the internet to perform this portion of the lab. Part 2It Takes a Licken’… Questions 1- 5 forDNA FINGERPRINTING BACKTOINDEX
GEL ELECTROPHORESISGel electrophoresis is a method that separates molecules on the basis of size, electric charge, and other physical properties. A gel is a colloid in a solid form. NEXT SLIDE
The term electrophoresis describes the migration of charged particle under the influence of an electric field. Electro refers to the energy of electricity. Phoresis, from the Greek verb phoros, means "to carry across." NEXT SLIDE
Gel electrophoresis refers to the technique in which molecules are forced across a span of gel, motivated by an electrical current. Electrodes at either end of the gel provide the driving force. A molecule's properties determine how rapidly an electric field can move the moleculethrough agelatinous medium. NEXT SLIDE
An individual's DNA is as distinctive as a fingerprint. This technique was used to assist in determining O.J. Simpson's life. DNA samples can be obtained from the trace amounts of blood or semen. These DNA samples can beseparatedusing gelelectrophoresis. NEXT SLIDE
The number and position of bands formed on each lane of gel is the actual genetic "fingerprint" of that DNA sample. The characteristics of certain segments of DNA vary from person to person and form a highly individual, detectable "genetic fingerprint." Developed only in the mid-1980s, genetic fingerprinting has rapidly become a widely used courtroom tool. NEXT SLIDE
In 1988 the first person in the United States was executed based on DNA technology. The likelihood that two individuals--other than identical twins--will have the same genetic fingerprint varies from about one in 800,000 to about one in 1 billion. By comparison, the probability that two individuals will have the same conventionalfingerprint isalso aboutone in 1 billion. NEXT SLIDE
But the genetic fingerprint has many other advantages over conventional fingerprints. It is unusual for police to find a high-quality fingerprint at a crime scene, but much more likely that they will find blood or semen. Furthermore, only a microscopically small sample is required for a positiveidentification. NEXT SLIDE
No relationship exists between the conventional fingerprints of parents and children, but the genetic fingerprints are closely related because the child receives half of her or his genetic information from each parent. Thus, half the bands in the child's genetic fingerprint come from the mother, and halffrom the father. NEXT SLIDE
This similarity can be used to establish paternity (or maternity) with a much higher degree of certainty than is possible with other techniques, such as a blood test. NEXT SLIDE
Another application for this technique involves the effort to determine whether bones unearthed seven years ago in Argentina are those of Joseph Mengele, the chief physician at the Auschwitz concentration camp who supervised the systematic extermination of about 4 millionJewish men, women,and children duringWorld War II. NEXT SLIDE
On behalf of the German government, Jeffreys extracted a small amount of DNA from one of the bones and compared it to DNA from Mengele's son, Rolf Jenckel, and Jenckel's mother. In April 1992, he reported that the bones were indeedMengele's, finallyclosing the searchfor the sadisticphysician. NEXT SLIDE
Click on the link below to go to the interactive lab on Gel Electrophoresis. You will be required to be connected to the internet to perform this portion of the lab. When you are finished with the lab be sure you answer Gel Electrophoresisquestions 1- 4. PERFORM THEGEL ELECTROPHORESIS Questions 1- 4GEL ELECTROPHORESIS BACKTOINDEX
PATERNITY TESTING The DNA present in hair root bulbs, spermatozoa or any nucleated tissue can be profiled. It is noteworthy that red blood cells lose their nuclei early in their life span but white blood cells remain nucleated. NEXT SLIDE
A few hair roots on a blunt instrument found in the possession of a crime suspect can be matched against an autopsy blood sample. Similarly seminal fluid in the vagina of a rape victim can be compared with DNA in the hair or white blood cells of a suspect. Hair root NEXT SLIDE
Since every cell within an individual contains the same DNA there is no need to match DNA from semen with semen or from blood with blood. Samples commonly examined for DNA in forensic cases include liquid blood, blood stains, semen, saliva, cellular tissue, hairroot bulbs andmouth swabs. NEXT SLIDE
In practice disputed parentage means disputed paternity since maternity is rarely in doubt. Disputes may arise under the following circumstances:1) A married man may allege that his wife has committed adultery, and that he is not the father of one or more of her children.2) A women who has illegitimate offspring may allege that a certain man is the father of that child in order to obtain an affiliation order against him and to ensure financial assistance with the child's upbringing. NEXT SLIDE
Submission to blood testing is usually agreed between the parties and court orders are seldom required. Consent is required, the age of consent being 16 but the court may draw inferences from the fact that a person has failed to comply withblood testing. NEXT SLIDE
Use of DNA profiling for such purposes is increasing since it more positively discriminating than exclusion by serology. The practicalities of blood testing involve adequate identification of the parties involved by their legal representativesand by meansof photographs. NEXT SLIDE
Click on the link below to go to the interactive lab on Paternity Testing. You will be required to be connected to the internet to perform this portion of the lab. When you are finished with the lab be sure you answer Paternity Testingquestions 1-2. PERFORM THEPATERNITY TESTING Questions 1-2 forPATERNITY TESTING BACKTOINDEX