Part+4

**Describe:** Restriction fragment length polymorphism (RFLP) is the difference between the size of homologous samples of DNA and the location of them. They were the first type of molecular markers. The markers are co-dominant and highly locus-specific. **Analyze:** RFLP's can arise from single nucleotide polymorphisms (SNP). In RFLP analysis, the DNA is cut into segments and they are separated by gel electrophoresis. RFLP process requires a large amount of DNA. **Apply:** Restriction fragment length polymorphisms can be used in many different things including diagnosis of certain diseases, DNA fingerprinting in forensic cases, genome mapping and paternity testing. It is used to diagnose genetic disorders like sickle-cell disease. Alleles for certain disorders were first detected by RFLPs. **Synthesize:** This makes me think of the game memory. You can only make a match if you have the same two cards. Just like that, you can only make a match if you have the same two bands of DNA. **Argue:** This is a positive thing because anything that can cure or help treat any disorder or disease has to be a positive thing.
 * Restriction Fragment Length [[image:rflp.gif width="367" height="434" align="right"]] Polymorphism **
 * Sources:** AP Biology textbook, http://www.ncbi.nlm.nih.gov/projects/genome/probe/doc/TechRFLP.shtml

**Gene Therapy ** **Describe:** Gene therapy is introducing genes into affected patients for therapeutic purposes. **Analyze:** There are two different types of gene therapy. They are germ line and somatic. The difference between these two types is that in germ line the cells are modified in gametes so that the changes will be heritable and in somatic the cells are injected into the patient's somatic cells so it will benefit them only. There must be vectors involved in gene therapy to help the genes get to the cell. The vectors can be retroviruses and other types of viruses. **Apply:** Gene therapy can be used to treat disorders that are caused by a single defected gene. A normal allele could be inserted into the cells of the affected tissue of the disorder. The cells that will be receiving the normal allele need to be cells that will continue to divide and multiply throughout the person's life. **Synthesize:** This makes me think of replacing dead batteries in something like a remote. You take out the dead batteries that make the remote not work and replace them with new batteries. This will make the remote functional again. **Argue:** Positive, it can treat disorders and replace mutated genes.

**Gene Therapy video**


 * Sources:** AP Biology textbook, http://ghr.nlm.nih.gov/handbook/therapy/genetherapy


 * Transgenic Animals (Genetically Modified Organisms ~ GMOS)[[image:pharming1.gif align="right"]] **

**Describe:** A gene from an animal of one genotype into the genome of another animal is a transgenic animal. In vitro means in an artificial environment outside of the living organism.

**Analyze:** Eggs from a female of a recipient species are fertilized in vitro. Cloned DNA is injected into the nuclei of the fertilized eggs. Some cells are taken up by this DNA and can then express this foreign gene. A surrogate mother has these engineered embryos implanted into her. If one of the embryos develops, the result is now a transgenic animal.

**Apply:** Transgenic animals can act as pharmaceutical factories. Human proteins can be made by this like how the human blood protein antithrombin can be inserted into the genome of a goat so that the protein is made in it's milk.

**Synthesize:** This reminds me of adding flour to cookie dough. If flour is added to the dough, you can tell if they are fluffy when the cookies are baked. This is like when a certain gene is added to a fertilized egg, the gene may end up showing up when the animal is born.

**Argue:** I think this is a negative thing because the genetic makeup of animals should not be messed with, they were created a certain way for a particular reason, and humans should not fool around with it. Other bad effects may include unpredictable results, animals may suffer pain and distress, and human protein from the transgenic animal may cause allergic reactions.

[|Transgenic Animals]

**Sources:** AP Biology Textbook, [], http://www.writework.com/essay/transgenic-animals-these-animals-genetically-engineered


 * Transgenic Plants (Genetically Modified Organisms ~ GMOS)[[image:Steps_in_Making_Transgenic_Plants.gif align="right"]] **

**Describe:** A transgenic plant is a plant that has been genetically modified by genetic engineering.

**Analyze:** A restriction enzyme cuts out a specific gene in a bacteria plasmid. A normal plant cell becomes genetically modified to carry the bacterial gene. The new gene will enable the genetically modified cell to produce the specific protein made by the gene.

**Apply:** Researchers are able to create plants that make human proteins for medical use and viral proteins for use as vaccines.

**Synthesize:** This reminds me of adding a bead or many beads to a bracelet to make it more appealing, like adding a particular gene to a plasmid in a plant to make the plant more appealing by having it be more healthy or resistant to different insects and diseases.

**Argue:** This is both a positive and negative thing. The positives of transgenic plants is that it can improve nutritional quality. The plants can also be mad insect, disease, and herbicide resistant. Some negatives include the potential risk of transgenes in commercial crops endangering non-target or native species. There is also a worry for the accidental mixing of transgenic with non-transgenic crops.

[|Transgenic Plants]

**Sources:** AP Biology Textbook, [], http://www.edocfind.com/en/ppt/Transgenic%20Plant%20procedure-1.html


 * Genetic Profiles (forensic testing)[[image:dna-finger-printing-technique.jpeg align="right"]] **

**Describe:** A genetic profile is genetic markers that can be analyzed for any given person to determine their unique genetic profile. Short tandem repeats are variations in length of genetic markers.

**Analyze:** To help determine someone's genetic profile, short tandem repeats are used. These units that are 2-5 base sequences are in specific regions of a genome and are tandemly repeated. Highly polymorphic regions that have short repeated sequences of DNA are used. Almost certainly, unrelated people have different numbers of repeated units, so STRs can be used to discriminate between unrelated individuals. The STR locations on a chromosome are targeted with a specific sequence primers. This is amplified using PCR (polymerase chain reaction). The result of the DNA fragments are separated and then detected using electrophoresis.

**Apply:** This can be used to compare DNA samples from the victim, a suspect, and a small amount of blood at a crime scene. An organization called The Innocence Project, is dedicated to overturn wrongful convictions and uses STR analysis to do this when revisiting old cases. As a result of the legal work and also forensic work done by this group, 18 innocent people have been released from prison as of 2006.

**Synthesize:** This process makes me think of braille because short sequences of dots are used to make specific words like short sequences of DNA are used in STR to help identify a specific person.

**Argue:** The are many positives and negatives of Genetic Profiling. Positives include that it is not as invasive, it can help reduce and reverse wrongful convictions and help to protect the innocent. Negatives of this though is it violates a person's right to privacy, many people could have access to and use of the data, and wrongful of convictions may end up taking place.

[|Genetic Profile]

**Source:** AP Biology Textbook, http://www.brighthub.com/science/genetics/articles/65420.aspx, http://www.dnajunction.com/tests/genetic-profiling.php