Applied Genetics: DNA Technology

& Genomics

Manipulating the code

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What can you change? Changing phenotype

The genes that are expressed The genes turned “on”

Changing genotype Your alleles, your DNA

code for the traits you have or carry

Controlled Breeding Mass selection

Choosing parents with the best traits for a cross (or mating) from a large selection of phenotypes “the gene pool”

Inbreeding Breeding of closely

related organisms Brother/sister Self-pollinated

plants results in Purebreds

Homozygous recessive, homozygous dominant

MM x MM mm x mm

Hybridization Using parents with 2 different traits to

produce new combinations of traits Mm x Mm

Results in “hybrid vigor” Offspring have better traits than either parent

Liger/Tigon

Zonkey

polyploidy

Condition of having more than 2 complete sets of chromosomes

Caused by genetic errors in mitosis

“Induced” by chemicals or radiation

Gene manipulation Based on knowledge of Human Genome

Project Examined over 6 bill. Nucleotide bases in 20-

30,000 genes! Location of genes on chromosomes established Once you know where the genes are, you can

change them!!

Genetic Engineering Directly changing the gene code of

organism Recombinant DNA - Combining DNA from 2

different organisms Creates a chimera or transgenic organism Must recognize coding sequences of genes

must understand how to turn genes on gene expression

Tools Genomic maps of DNA so you know

where genes are on chromosomes Genomic libraries of genetic

information Restriction Enzymes

Enzyme scissors that cut the DNA molecule Ligase – enzyme glue

Plasmid A bacterial gene that is easy to work with

Benefits of Genetic Engineering

Make drugs easily & cheaply, i.e. insulin Make vaccines New and useful chimeras

genetically engineered crops for disease or insect resistance, increased yield

Save DNA from endangered species What else???

Risks? Genethics? Moral and ethical implications of genetic

engineering Cloning a super race Frankenfoods Bringing back the dead What are YOUR concerns?

Gene Therapy & cloning How to transfer the correct gene into an

affected individual? Cloning vectors

A carrier of genetic info. used to transmit genetic information

Cloning Making exact copies of DNA, making exact

copies of YOU Mitosis, binary fission, vegetative propagation,

regeneration Recall, all somatic cells contain all DNA

information your body needs to make you i.e., a cheek cell contains the DNA to become a

heart cell

DNA Fingerprinting Comparison of DNA found in blood samples,

tissue samples, etc. to identify individuals for classification, criminology, paternity suits, etc.

Can determine diseases & genetic defects Tracing family history & evolution

DNA fingerprinting

Restriction Fragment Length Polymorphism (RFLP) Cut DNA of individual with

restriction enzymes Separate fragments in gel

electrophoresis compare - 5 banding images is a

match