FRIDAY, APR 4TH, 2014

Did you know…

A lobster has a sense of smell ~1000x keener
than a human.

Frogs eat their skin after they shed it.
YOUTUBE FRIDAY

http://www.youtube.com/watch?v=dqoPXC60l
_s

http://www.youtube.com/watch?v=puipmbc_3
CY
GENETIC ENGINEERING


Humans purposefully
change DNA
E.g., luciferase gene
in fireflies inserted into
tobacco plant DNA
SELECTIVE BREEDING

Humans cross/breed 2
orgs of same species

Possess most desirable
traits


Farmers cross 2
tomatoes b/c heartiest &
most disease-resistant
E.g. horses, dogs, crops
INBREEDING

Continual breeding of orgs w/ same heritage
 Small,
elite pop

I.e., maintain a breed of dogs (e.g., poodles)

Risky: offspring often
inherit 2 recessive alleles
for genetic disorder
HYBRIDIZATION

Cross 2 different orgs
 Best
traits together into 1 org
E.g., loganberry = raspberry + blackberry
 E.g., peppermint = spearmint + water mint

TRANSGENIC ORGANISM

Contains DNA from another species
 “Across”

orgs
Used in production
of human insulin
or in bacteria that
break down oil
GENETICALLY MODIFIED ORGS, “GMO”

Transgenic crops

“Golden rice:” vitamin A gene inserted into rice
DNA
 Staple
food for billions
 Vitamin A important for eye
sight (found in carrots)
CLONING

Genetically identical org coming from 1 parent
(asexual reproduction)

Dolly: 1st mammal (sheep)
cloned (1997)
 Only
lived 6 yrs
ANIMALS THAT HAVE BEEN CLONED






Camel
Carp
Cat
Cattle
Dog
Ferret






Frog (tadpole)
Fruit Flies
Gaur
Goat
Horse
Mice






Mouflon  Sheep
Mule
 Water Buffalo
Pig
 Wolf
Rabbit
 And more!
Rat
Rhesus Monkey
GENETICS ENGINEERING + HUMANS
1. TESTING FOR GENETIC DISORDERS

Scan DNA for specific sequences for
disorder/disease

100+ genetic disorders can be tested
 E.g.,
cystic fibrosis (CF), Tay-Sachs disease
2. DNA FINGERPRINTING

Identify by comparing DNA sequence lengths
 Analyze

No individual is exactly the same
 EXCEPT

introns (filler space)
identical twins
Uses:
 Paternity
testing
 Criminal identification
 https://www.youtube.com/watch?v=PSwlCk_Z02c
2. DNA FINGERPRINTING
1.
Restriction enzymes cut DNA into small pieces
2.
DNA pieces separated by size on
electrophoresis gel

3.

Shorter pieces move faster/farther than long
pieces
Compare DNA piece lengths
http://www.pbs.org/wgbh/nova/education/bo
dy/create-dna-fingerprint.html
3. HUMAN GENOME PROJECT (2000)

Purposes:
 Analyze
human DNA sequence for genes
 Screen individuals for specific genes
 Develop gene therapies

Difficult to analyze b/c
most of genome is
introns/filler sequence
4. GENE THERAPY

Swap faulty gene of genetic
disorder for normal, working
gene

Use viral vector
 Virus
inserts DNA sequence into host genome
 New proteins expressed

http://www.dnatube.com/video/27687/Explan
ation-of-Recombination-Genetic-Engineering