Download Gene Technology

Applied Genetics:
DNA Technology
& Genomics
Manipulating the code
Text Ch 31
What can you change?
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Changing phenotype
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The genes that are
expressed
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The genes turned “on”
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Changing genotype
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Your alleles, your DNA
code for the traits you have
or carry
Controlled Breeding
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Mass selection
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Choosing parents with the best traits for a cross (or
mating) from a large selection of phenotypes
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“the gene pool”
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Inbreeding
Breeding of closely
related organisms
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Brother/sister
Self-pollinated plants
results in Purebreds
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Homozygous recessive,
homozygous dominant
MM x MM
mm x mm
Hybridization
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Using parents with 2 different traits to produce new
combinations of traits
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Mm x Mm
Results in “hybrid vigor”
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Offspring have better traits than either parent
Liger/Tigon
Zonkey
polyploidy
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Condition of
having more than
2 complete sets of
chromosomes
Caused by genetic
errors in mitosis
“Induced” by
chemicals or
radiation
Gene manipulation
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Based on knowledge of Human Genome Project
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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
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Directly changing the gene code of organism
Recombinant DNA - Combining DNA from 2
different organisms
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Creates a chimera or transgenic organism
Must recognize coding sequences of genes must
understand how to turn genes on
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gene expression
Tools
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Genomic maps of DNA so you know where
genes are on chromosomes
Genomic libraries of genetic information
Restriction Enzymes
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Enzyme scissors that cut the DNA molecule
Ligase – enzyme glue
Plasmid
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A bacterial gene that is easy to work with
Benefits of Genetic Engineering
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Make drugs easily & cheaply, i.e. insulin
Make vaccines
New and useful chimeras
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genetically engineered crops for disease or insect
resistance, increased yield
Save DNA from endangered species
What else???
Risks? Genethics?
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Moral and ethical implications of genetic engineering
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Cloning a super race
Frankenfoods
Bringing back the dead
What are YOUR concerns?
Gene Therapy & cloning
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How to transfer the correct gene into an affected
individual?
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Cloning vectors
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A carrier of genetic info. used to transmit genetic information
Cloning
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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
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i.e., a cheek cell contains the DNA to become a heart cell
DNA Fingerprinting
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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
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