Genetic Engineering the manipulation of living organisms for human use Chapter 13

Breeding strategies Selective breeding: only certain individuals with certain traits are selected to reproduce Selective breeding: only certain individuals with certain traits are selected to reproduce Inbreeding: crosses individuals with similar traits Inbreeding: crosses individuals with similar traits Hybridization: crosses individuals with different traits; tend to be hardier and healthier Hybridization: crosses individuals with different traits; tend to be hardier and healthier

Manipulating DNA Genetic engineering: making changes in the DNA code of an organism Genetic engineering: making changes in the DNA code of an organism Restriction enzymes: cut the DNA at specific sites by recognizing certain DNA sequences Restriction enzymes: cut the DNA at specific sites by recognizing certain DNA sequences –produces more manageable pieces of DNA to separate and analyze Gel electrophoresis: separates DNA fragments through a gel using electricity; creates a “DNA fingerprint” Gel electrophoresis: separates DNA fragments through a gel using electricity; creates a “DNA fingerprint” –Identifying criminals –Paternity (who is the father of the baby?)

Gel Electrophoresis

DNA fingerprinting method of DNA analysis which identifies individuals by examining DNA fragments method of DNA analysis which identifies individuals by examining DNA fragments Steps Steps –sample of DNA is cut using restriction enzymes –fragments are separated using electrophoresis to create a pattern of bands (negatively-charged DNA moves towards positive-end of apparatus) –Shortest segments travel the furthest (easier to move through gel)

Using DNA Recombinant DNA: the manipulation of specific genes in the cells of living organisms causing them to produce new or unusual substances Recombinant DNA: the manipulation of specific genes in the cells of living organisms causing them to produce new or unusual substances Polymerase Chain Reaction (PCR): uses DNA polymerase to create thousands of copies of a gene Polymerase Chain Reaction (PCR): uses DNA polymerase to create thousands of copies of a gene

Application of Gen. Eng. Transgenic Organisms Transgenic Organisms –Contain DNA from another species –Example: insulin-producing bacteria –52% of soybeans, 25% of corn are genetically-modified (“GMO”)

Application of Gen. Eng. Cloning Cloning –Clone: member of a population of genetically identical cells that are produced from a single cell –Somatic Cell Nuclear Transfer In 1997, Ian Wilmut presented “Dolly”, the first cloned sheep In 1997, Ian Wilmut presented “Dolly”, the first cloned sheep content/tech/cloning/whatisclo ning/ content/tech/cloning/whatisclo ning/ content/tech/cloning/whatisclo ning/ content/tech/cloning/whatisclo ning/

Steps of Cloning

Human Genome Project An ongoing effort to analyze the human DNA sequence An ongoing effort to analyze the human DNA sequence Started in 1990, completed in 2000 Started in 1990, completed in 2000 Different scientists studied random fragments of DNA then combined their data Different scientists studied random fragments of DNA then combined their data Humans have approximately 35,000 genes Humans have approximately 35,000 genes