Genetic Engineering: Breeding, Hybridization, Inbreeding, Mutations, Techniques, Slides of Biology

Download Genetic Engineering: Breeding, Hybridization, Inbreeding, Mutations, Techniques and more Slides Biology in PDF only on Docsity! Genetic Engineering Chapter 13 Docsity.com Selective Breeding  refers to the process of allowing only those animals with the desired characteristics to reproduce.  Nearly all domestic animals are the products of selective breeding Ex. Dogs (all the same species)  Do humans use selective breeding? Docsity.com Mutations  We can increase the genetic variation in a population by causing mutations, which are the ultimate source of all genetic variation. Docsity.com Mutations  mutations can be increased by exposure to chemicals and radiation  remember most mutations are harmful, chances are that a few will cause desirable characteristics that are not found in the general population.  Oil-eating bacteria Docsity.com Genetic Engineering  refers to making changes in the DNA code of a living organism  Examples: SCID mice  Insulin producing bacteria  pGlO Docsity.com TN th | mm maa AUAMNOTONU a A pF Hit HUN ONUDOauEHIN roneM ma ULC ONO DHA Replicated cleotide Mm base Polymerization N Annealing me Mi NUD IMTOO NO NM DY HOTT T ANTON inh lng OULD UDO mm il) & oO O Q. Ga © 2) ©. ® pe) ep) Denaturation Steps of PCR  1) Denature DNA- heat to 95°C  2) Anneal Primers- cool to 55°C  3) Polymerization- 72°C using Taq Polymerase Docsity.com ce 0 be ar ied \ {fragment of a chromosome) ST ° ecseanannraenseey ¥ ; 16 copies eC ve B copies 2 er / =< oo ada ona <2 79 <= polymer ae \ ~S mE ° cme mmr vat ~S mE Inevbate \ — oo ° oor / om <" I= _- ma x 7S mt I= \gu- ~S mE I= - aS oo Ir _ _ ~S IIE PCR to detect HIV • PCR detection of HIV genomes may occur before the appearance of anti-HIV antibodies in patient blood • viral DNA/RNA only represents minute proportion of total cell DNA • Only a small fraction of blood cells are infected (1/10,000) • also require high degree of specificity while also targeting conserved regions of DNA to guard against high level of genetic variability characteristic of retroviruses • High risk of cross-contaminating sample with small amounts of amplified DNA from previous sample requires extra precautions to prevent false-positives • PCR can detect 10-20 copies of viral DNA from 150,000 human cells Docsity.com PCR can be more rapid and accurate than other tests • Diagnosis of the middle ear infection known as otitis media. The technique has detected bacterial DNA in children's middle ear fluid, signaling an active infection even when culture methods failed to detect it. • Lyme disease, the painful joint inflammation caused by bacteria transmitted through tick bites, can be diagnosed by detecting the disease organism's DNA contained in joint fluid. • PCR is the most sensitive and specific test for Helicobacter pylori, the disease organism now known to cause almost all stomach ulcers. • PCR can detect three different sexually transmitted disease organisms on a single swab (herpes, papillomaviruses, and chlamydia). Docsity.com OJ Simpson Murder Trial The case against Mr. Simpson was built in part on evidence from polymerase chain reaction (PCR) analysis of blood evidence. Docsity.com PCR in Forensics Crucial forensic evidence may be present in very small quantities. • often too little material for direct DNA analysis • but PCR can generate sufficient DNA from a single cell • PCR also possible on extensively degraded DNA • examples include DNA from single dried blood spot, saliva (on cigarette butt), semen, tissue from under fingernails, hair root Other advantages of PCR in forensic science are: • relatively simple to perform and simple to standardize • results obtainable within 24 hours The major legal problem with PCR is that identification is made from copied DNA rather than from the original material. Another potential problem: cross-contamination between samples. Docsity.com PCR excludes but does not include DNA typing is only one of many pieces of evidence that can lead to a conviction, but it has proved invaluable in demonstrating innocence. Dozens of such cases have involved people who have spent years in jail for crimes they did not commit. One example is Kirk Bloodsworth. The Maryland waterman was wrongly imprisoned for almost nine years for the rape and murder of a 9-year-old girl, but was freed in 1993 with the aid of PCR. Even when evidence such as semen and blood stains is years old, PCR can make unlimited copies of the tiny amounts of DNA remaining in the stains for typing, as it did in Bloodsworth's case. Docsity.com = DNA Sampie { 41. Restriction enzymes cleave DNA into smaller segments of various sizes. 2. DNA segments are loaded into wells in a porous gel. The gel floats in a buffer solution within a chamber between two electrodes. 3. When an electric current is nT | passed through the chamber, DNA fragments move toward © it " Q ® the positively-charged cathode. mE ol ~~ 4. Smaller DNA segments move faster and farther than larger DNA segments. Foreign DNA to be inserted ~-——__ ag { Joining Plasmid vector Se Recombinant DNA molecule ~——, Introduction into host cell / Ge SS Selection for cells containing recombinant DNA molecules by growth in the presence of antibiotic FIGURE 5-11 The cloning of DNA in a plasmid. Docsity.com Cloning  the process of producing an identical organism from a single cell.  Most commonly used with bacteria  Some use in eukaryotes Docsity.com