r 13 apte Ch GENE Y NOLOG TECH

r 13 apte Ch GENE Y NOLOG TECH

Section 1: DNA TECHNOLOGY-Tools of DNA Positive ID at a crime scene Improvement of food crops Human predisposition for disease Research treatments for genetic diseases

DNA Identification No two human beings are identical genetically – except identical twins Human beings have pretty much the same DNA except for 0. 1% Because of this difference, we can compare samples of humans for paternity, providing evidence, tracing human origins, identifying remains

Noncoding DNA We only use about 2% of our DNA The remaining 98% is called noncoding DNA This DNA contains many long, repeating varying nucleotide sequences called variable number tandem repeats – VNTR CACACA CACACA

Noncoding DNA, cont. The pattern of repeating nucleotides varies tremendously in the human population and can be used to make up a DNA profile

Steps in DNA Identification DNA Extraction (isolation) PCR – polymerase chain reaction – the molecular photocopying process http: //learn. genetics. utah. edu/content/labs/pcr/

Steps, cont. – RE’s Restriction enzymes – the molecular scissors Enzymes that can cut (hydrolyze) DNA at specific sites. Current DNA technology is totally dependent on restriction enzymes. Restriction enzymes are endonucleases – they cut within the DNA

Steps, cont. Bacterial enzymes – used to cut bacteriophage DNA (viruses that invade bacteria) – why? Different bacterial strains produce different restriction enzymes The names of restriction enzymes are derived from the name of the bacterial strain they are isolated from

Steps, cont. Titles of restriction enzymes are derived from the first letter of the genus + the first two letters of the species of organism from which they were isolated. Eco. RI - from Escherichia coli Bam. HI - from Bacillus amyloliquefaciens Hind. III - from Haemophilus influenzae

Steps, cont.

Steps, cont. Using this piece of DNA, cut it with Eco RI G/AATTC GACCG/AATTCAGTTAATTCG/AATTC

Steps, cont. Sticky ends – Creates an overhang. Bam. H 1 Blunts- Enzymes that cut at precisely opposites without overhangs. Sma. I is an example of an enzyme that generates blunt ends

Steps, cont. GE Gel Electrophoresis – the molecular sieve Separates nucleic acids or proteins based on size and charge DNA fingerprinting – Banding pattern of the fragments of cut DNA on a special gel medium (agarose)

Steps, cont. GE http: //learn. genetics. utah. edu/content/labs/gel/

Steps, cont. GE

DNA Fingerprinting A powerful tool to analyze VNTR Odds are 1/100, 000, 000 that any two people will have the same genetic fingerprint!!!

Recombinant DNA The process of altering genetic material to make new substances – genetic engineering The product is called recombinant DNA

Cloning Vectors Many copies of a desired gene can be cloned and its product harvested This is accomplished by using a cloning vector – an organism that contains the desired gene and can multiply rapidly – this organism is usually a bacterium Vector = carrier http: //www. bioteach. ubc. ca/Teaching. Resources/App lications/GMOpkg. JKlose. GLampard 2. swf

Probes A strand of DNA or RNA that is radiolabeled It is used to “fish” for the desired gene when either carrying out recombination, or identifying unknown DNA

Section 2: The Human Genome Huge research project, conducted over 13 years, sequenced and identified 20 -25, 000 human genes Findings include: 2% coding DNA, RNA useful in regulating gene expression, transposons shuffle to make new genetic combinations

Section 3: Genetic Engineering Gene therapy – treat a genetic disorder by inserting a functional gene CFTR gene in cystic fibrosis, a temporary fix Gene inserted into a nonpathogenic virus and introduced into nasal spray Not completely successful; lung tissue is deep, cells slough off, rejection responses

Cloning Stimulate to divide; implant into another female sheep Mammary cell nucleus of one sheep Insert it into an anucleated egg cell from another sheep

HELLO DOLLY!!! Dolly died prematurely as she had short telomeres = ends of chromosomes – like aglets! Currently animals can be cloned to grow up organs for human transplants

Other applications GMOs – genetically modified organisms, crops Increase yield, make crops weather and pest resistant, increase nutritional value Controversy related to genetically modified (GM) food : risk of harm from GM food, whether GM food should be labeled, the role of government regulators, the effect of GM crops on the environment, the impact of GM crops for farmers, the role of GM crops in feeding the growing world population

GM foods, cont. Soy, corn, dairy Buy organic, 100% grass fed beef Buy local PLU codes – 5 numbers beginning with a 9 = organic; 4 numbers = conventional; 5 numbers beginning with an 8 = GM