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BIOSPHERE

The Thin layer of
LIFE on the Earth.
3 PARTS:
 ATMOSPHERE (air)
 HYDROSPHERE (water)
 LITHOSPHERE (crust)
Pic from: http://www.ucar.edu/learn/images/athylibi.gif
CHAPTER 13
GENE TECHNOLOGY
http://www.guardian.co.uk/commentisfree/2008/jan/15/chewonthis
http://www.ekac.org/swissprot/swissprot.html
DNA IDENTIFICATION
Except for identical twins no two people are
genetically alike
 .10 %of the human genome varies between
people!!
 DNA can be used in identifying human
remains, providing evidence in criminal
cases, and determining paternity

TECHNOLOGY VOCABULARY
Noncoding DNA – DNA that doesn’t code for a
protein “junk” DNA
 Polymorphism-variations in the length of “junk”
DNA
 VNTR- variable number tandem repeats
number of repeats determines what is different in
individuals & this is what forensic scientists look at in
DNA profiling
 Ex: CACACACACACA-can repeat a few times or many
times

STEPS IN DNA IDENTIFICATION
1. Isolate the sample and make copies
 2. Cut the DNA into shorter fragments that
contain known VNTR’s
 3. Sort the DNA by size (use gel
electrophoresis)
 4. Compare patterns of the unknown DNA
sample to a known DNA sample

P 1: ISOLATE AND COPY
Polymerase chain reaction – technique used to
make copies of DNA fragments
 You can make millions of copies

authorjenniferchase.com
18mp.army.mil
P 2: CUT DNA INTO SHORTER FRAGMENTS

Restriction enzymes-bacterial proteins that
recognize a specific sequence of DNA and cut
the DNA in specific sequences
biotechlearn.org.nz
3. SORT THE DNA BY SIZE

Fragments of DNA are studied using a technique
called gel electrophoresis
 Separates molecules according to size &
electrical charge
 The smaller fragments move faster and farther
than the larger fragments
en.wikipedia.org
biology.arizona.edu
DNA Fingerprint- resulting pattern of bands
4. COMPARE PATTERNS OF KNOWN DNA TO
UNKNOWN DNA

Biologists use subtle genetic differences in
DNA to identify each individual
•DNA fingerprinting
compares between 5-13
VNTR’s to produce a
profile
•Accuracy: odds that 2
people will share the same
DNA profile are about one in
one billion!!
baronescience.info
IMPORTANT VOCABULARY
Genetic engineering-altering the genetic material
of cells or organisms to allow them to make new
substances
 Clone – exact copy of DNA segment, cell, or
complete organism
 Plasmid – small rings of DNA found naturally in
some bacterial cells
 Vector – any agent, such as a plasmid or virus that
can carry a DNA molecule from 1 organism to
another

MAKING RECOMBINANT DNA
Recombinant DNA – when DNA from 2
different organisms is joined
To do this: Insert a gene for an enzyme or
hormone into a genome of bacteria or
another organism
- the organism produces new proteins that it
couldn’t before
- examples include insulin and HGF

II. HUMAN GENOME PROJECT
A research effort to
sequence all 3.3 billion
nucleotides of the
human genome
 Determine locations of
every gene on every
chromosome!!

bioinformaticonline.com
GOALS FROM WEBSITE
HTTP://WWW.ORNL.GOV/SCI/TECHRESOURCES/HUMAN_GENO
ME/HOME.SHTML
identify all the approximately 20,000-25,000
genes in human DNA
 determine the sequences of the 3 billion
chemical base pairs that make up human DNA
 store this information in databases
 improve tools for data analysis
 transfer related technologies to the private
sector
 address the ethical, legal, and social issues
(ELSI) that may arise from the project.


There are about 8 million single nucleotide
polymorphisms (places where individuals differ
by only 1 nucleotide – used in DNA
fingerprinting)
APPLICATIONS

Discovered specific genes responsible genes
responsible for several genetic disorders
 Researchers
can improve diagnoses and
treatments for more than 4,000 disorders
GENETIC ENGINEERING
Medical Applications – gene therapy, cloning,
vaccines
B. Agricultural Applications – genetically modified
crops
C. Bioethics – the study of ethical issues related
to DNA technology
MEDICAL APPLICATIONS

Gene Therapy – introducing a gene into a
patients cell to treat a genetic disorder
 Works
best with disorders that result from the loss
of a single protein
 Ex.
Cystic fibrosis, Hemophilia, Sickle Cell Anemia
Steps involved in gene therapy
1. Isolate the functional gene
 2. Insert healthy gene into a viral vector
 3. Introduce the recombinant virus to the patient

http://www.curesf.org/wpcontent/uploads/2012/02/gene-therapy.gif
MR. GREEN GENES (2008)
http://today.msnbc.msn.com/id/27338236#.T1aQ-TGPUQo
The glow in the dark cat is the result of a
genetic experiment.
 Researchers wanted to see if he was a
transgenic cat – immune to FIV

Audubon Center for Research of Endangered
CLONING
Began in the 1990’s with cloning whole
organisms such as sheep and mice
 Dolly was the first cloned mammal born in
1996

 She
suffered premature ageing and disease and
died at 6 yrs old possibly from having short
telomeres.
randomworldofjen.blogspot.com
CLONING – HOW IT WORKS
1.
Egg has nucleus(with its DNA) removed
2.
Cell from organism to be cloned,
such as a skin cell, is collected.
3. Empty egg & whole skin cell are
placed close together & electric
shocked, which makes them fuse
together.
4.
The new cell contains DNA from only
1 cell (the skin cell, not the egg) & is
grown
It becomes a new baby.
AGRICULTURAL APPLICATIONS
Develop new strains of plants called genetically
modified (GM) crops
 Increase the amount produced and improve
nutrition

 In
Asia researchers added genes to rice to over
come the iron deficiencies
FIRST GM FOOD
•The first commercially grown genetically
modified food crop, a tomato, was made
more resistant to rotting, by adding a gene.
•1994- Approved by FDA –decided it did not constitute
a health hazard, and did not need special labeling.
Calgene was allowed to release it into the market.
Welcomed by consumers who purchased the fruit at
two to five times the price of standard tomatoes.
Company bought by Monsanto in 1995.
Monsanto Company is a multinational agricultural
biotechnology corporation & is the world's leading producer
of the herbicide Roundup.
Monsanto is also by far the leading producer of genetically
engineered (GE) seed, holding 70%–100% market share for
various crops.
GM MILK COWS
• Scientists
introduced a new
gene into milk cows that
could get them to produce
human milk
•Healthier alternative for
formula?
FISHY STRAWBERRIES
Flounder is a fish that can withstand
icy cold temperatures.
 Scientists took the gene in the fish that
Produces an antifreeze & inserted it into
a plasmid of a bacterium
 The bacterium infected the strawberry &
the flounder antifreeze gene entered the
strawberry’s DNA
 The new GM strawberry cells are grown
Into new plants that have strawberries
which make a protein that keeps the fruit
from frost damage.

floundergigging.co
GM MOSQUITOS
Stop mosquito born
diseases like malaria buy
creating insects that are
less infectious
 Trying to get them
released in the Key West
to help eradicate dengue
fever and the mosquitos
that spread it

FEATHERLESS CHICKEN
In Israel scientists have
discovered a way to make a
more convenient type
chicken – one that’s easier
to process
 Grows faster because it
doesn’t have to use energy http://oddanimals.com/featherless-chicken/
to create feathers
 Only lives in warmer
climates

ETHICAL ISSUES
Is the food safe to eat?
 Is the food harmful to the environment?
 What are your thoughts on gene therapy?
 Cloning of human embryos?
Decisions must be made by both scientists
and the public
