Can DNA profiling identify the source of a sample with absolute certainty? Because any two human genomes differ at about 3 million sites, no two persons (except identical twins) have the same DNA sequence. Unique identification with DNA profiling is therefore possible if enough sites of variation are examined. However, the systems used today examine only a few sites of variation. Nonetheless, even with today’s technology, which uses three to five loci, a match between two DNA patterns can be considered strong evidence that the two samples came from the same source. DNA profiling in criminal cases has been a useful tool in establishing both guilt and innocence. Originally, DNA databases contained only the profiles of convicted felons. Over time, however, law enforcement agencies have expanded the collection and use of DNA profiles, and these new policies are causing controversies, once again illustrating how the availability and use of genetic technology is often ahead of consensus on how and when this technology should be used. One of these new policies is postarrest DNA collection. At this writing, 18 U.S. states as well as the federal government allow the collection of DNA samples after an arrest but before conviction. These profiles become part of the state’s DNA database, which is often searched for evidence in cold cases. Courts across the country have ruled for and against the use of such samples. In 2012, the Maryland Court of Appeals ruled that the collection of DNA samples from someone who has been arrested but not convicted is unconstitutional and violates an individual’s right to be free from unreasonable search and seizure. The case began when a DNA sample was taken from Alonzo Jay King, Jr., who was arrested in 2009 for assault. In a database search, the DNA profile matched that taken from a 2003 unsolved rape. Based on the results of the database search, the man was sentenced to life in prison. The rape conviction was reversed, and the case was sent back to a lower court. As a result, some 16,000 DNA profiles collected postarrest but preconviction since 2009 cannot be used pending appeal of this decision. Before the court decision, postarrest DNA profiles were used in 65 arrests that resulted in 34 convictions, with an additional 12 cases pending. Supporters of postarrest DNA profiling claim that taking a DNA sample by a cheek swab is noninvasive and no different from taking someone’s fingerprints. Opponents claim that because DNA samples can be used to determine much more than a DNA profile, they are a threat to privacy, and that because minorities are more likely to be arrested, the practice is discriminatory. Would you object if you were arrested for a minor offense, such as a traffic violation, and ordered to provide a DNA sample?

Can DNA profiling identify the source of a sample with absolute certainty? Because any two human genomes differ at about 3 million sites, no two persons (except identical twins) have the same DNA sequence. Unique identification with DNA profiling is therefore possible if enough sites of variation are examined. However, the systems used today examine only a few sites of variation. Nonetheless, even with todays technology, which uses three to five loci, a match between two DNA patterns can be considered strong evidence that the two samples came from the same source. DNA profiling in criminal cases has been a useful tool in establishing both guilt and innocence. Originally, DNA databases contained only the profiles of convicted felons. Over time, however, law enforcement agencies have expanded the collection and use of DNA profiles, and these new policies are causing controversies, once again illustrating how the availability and use of genetic technology is often ahead of consensus on how and when this technology should be used. One of these new policies is postarrest DNA collection. At this writing, 18 U.S. states as well as the federal government allow the collection of DNA samples after an arrest but before conviction. These profiles become part of the states DNA database, which is often searched for evidence in cold cases. Courts across the country have ruled for and against the use of such samples. In 2012, the Maryland Court of Appeals ruled that the collection of DNA samples from someone who has been arrested but not convicted is unconstitutional and violates an individuals right to be free from unreasonable search and seizure. The case began when a DNA sample was taken from Alonzo Jay King, Jr., who was arrested in 2009 for assault. In a database search, the DNA profile matched that taken from a 2003 unsolved rape. Based on the results of the database search, the man was sentenced to life in prison. The rape conviction was reversed, and the case was sent back to a lower court. As a result, some 16,000 DNA profiles collected postarrest but preconviction since 2009 cannot be used pending appeal of this decision. Before the court decision, postarrest DNA profiles were used in 65 arrests that resulted in 34 convictions, with an additional 12 cases pending. Supporters of postarrest DNA profiling claim that taking a DNA sample by a cheek swab is noninvasive and no different from taking someones fingerprints. Opponents claim that because DNA samples can be used to determine much more than a DNA profile, they are a threat to privacy, and that because minorities are more likely to be arrested, the practice is discriminatory. What are your thoughts on the collection and use of postarrest DNA profiles?

DNA from 100 unrelated individuals from one population of Chinook salmon were amplified at a single microsatellite locus, and run on an agarose gel. The results from gel electrophoresis shows three different fragment lengths (i.e. alleles/band positions) corresponding to 3 alleles; Allele F (250bp), Allele R (180bp), and Allele Y (100bp). The numbers at the top of each lane is the number of fish observed with that particular genotype or banding pattern in the population. Note that a single band means a homozygote for that allele (band size). a) Calculate the allele frequency for Allele Y. (b) Calculate the genotype frequencies for the following genotypes: FF, FR, and RY. (c) What is the expected number of Chinook salmon with homozygous genotype for allele Y in the study population? (d)What is the name of the statistical test that you could conduct to test whether this population of Chinook salmon is in Hardy Weinberg Equilibrium

1.) What characteristics of VNTR and STR make them useful for DNA fingerprinting? 2.) How does PCR minimize the problems associated with degraded DNA? 3.) What factors can cause DNA to become degraded? 4.) If Ethidium bromide was not added to a gel, what would happen? 5.) How can you tell if an individual is heterozygous for the D1S80 marker? 6.) If a negative control produces a band, what does this indicate? 7.) In an experiment, a student’s sample amplified for D1S80 produced 3 bands. It was the only DNA sample run on the gel. The student knows that there was no problem with the Thermocycler or primers because the other students in the class had the expected results of only one or two bands. What is the most likely explanation for these results?

What is meant by the term DNA fingerprinting?

The current state-of-the-art in forensic DNA profiling involves the PCR-amplification and analysis ofshort tandem repeats, STRs, in the human genome. This approach has many distinct advantages.Please list and explain three of those advantages.

DNA fingerprinting questions: ( Please label each lane so I know which one you refer to) Please explain vividly so I can understand: •Explain each lane, by analyzing the band pattern and concluding whether it's homozygous or heterozygous for the presence of Alu at the PV92 locus. •Literature states Alu insertions at PV92 locus are most common in the Asian population (+/+) and mostly not found in Europeans, Americans (-/-) Reference: https://www.mediafire.com/file/s3nr36ow4bw4udw/DNA+Fingerprinting.docx/file

Could actual fi ngerprints taken from human fi ngers be used to perform a DNA fi ngerprint? Explain.

Below is an image of the results of a gel electrophoresis experiment. Lanes 1-4 contain amplified DNA fragments and Lane 5 contains the DNA size marker (DSM). From this image and by only using Lanes 1- 4 which lane matches each description below? a) This lane contains the largest DNA fragment: b) This lane contains the smallest DNA fragment: c) This lane contains a 2.5 kbp DNA fragment: 42 | || ||| | || 12 kb 9.5 kb 6.5 kb 4 kb 2 kb ***

What is DNA fingerprinting? Mention its application.

Why are entire genomes not used for DNA profiling?

In a PCR-based crime scene investigation, similar to the one presented in the lab module with Brother Y and Brother X, there is a sample of DNA from a crime scene that is likely to belong to the guilty party. Based on the gel photo below, which shows the results of an electrophoresis gel following PCR amplification at one locus of 5 DNA samples - one crime scene sample and 4 suspects - which suspects can be excluded from this investigation? [Keep in mind that it is not possible for a heterozygous person to leave only one allele at a crime scene. If any one allele does not match, then that suspect is eliminated.] Choose all that apply.

How is the color of the spot coverted into useful data if data is collected from a Vicrochip DNA microarray that's from the colors of spots that illuminate when the spots have a laser shine on them? From the following which one is the best option The color of the spot is converted to a number that represents the intensity of green or red, so that the numerical intensity values can be compared between spots by a computer program The color of the spot is bright so that it can be interpreted visually by trained scientists The color of the spot is present on the chip, counted and a ratio of red-yellow and green-yellow is calculated which can be done by hand The color of the spot can't be converted None of the above

Solution Summary: The author explains that DNA samples are collected to construct a DNA profile, and criminal cases and paternity cases can be studied with the help of DNA profiles.

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