Transcript 15.2

Genetic Technology
15.2,15.3
6 slides with notes to write down
Copying DNA- Extracting DNA
using Gel Electrophoresis
Gel electrophoresis – separates DNA according to size of fragments
DNA Fingerprinting
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Collect Tissue
Amplify sample (PCR)
Add restriction enzymes (cut DNA)
Run Gel Electrophoresis
Analyze/compare bands
Personal Identification
– In DNA fingerprinting, restriction enzymes first
cut a small sample of human DNA into
fragments containing genes and repeats. Note
that the repeat fragments from these two
samples are of different lengths.
– Next, gel electrophoresis separates the
restriction fragments by size.
Forensic Science
–
The precision and reliability of
DNA fingerprinting has
revolutionized forensics—the
scientific study of crime scene
evidence.
–
DNA fingerprinting has
helped solve crimes, convict
criminals, and even overturn
wrongful convictions.
–
To date, DNA evidence has
saved more than 110
wrongfully convicted prisoners
from death sentences.
Transgenic Organisms
– The universal nature of the genetic code makes it
possible to construct organisms that are
transgenic, containing genes from other species.
– Transgenic organisms can be produced by the
insertion of recombinant DNA into the genome of a
host organism.
– Like bacterial plasmids, the DNA molecules used
for transformation of plant and animal cells contain
genetic markers that help scientists identify which
cells have been transformed.
Transgenic Plants: Transforming
a Plant with Agrobacterium
Cloning Animals—Nuclear
Transplantation
Clone – a genetically identical organism
Treating Disease —
One Example of Gene Therapy
– To deliver therapeutic genes to target cells
researchers engineer a virus that cannot
reproduce or cause harm.
Human Genome Project
• John Craig Venter: Celera Genomics
• Cells are the fundamental working units of
every living system. All the instructions
needed to direct their activities are contained
within the chemical DNA (deoxyribonucleic
acid).
• DNA from all organisms is made up of the
same chemical and physical components. The
DNA sequence is the particular side-by-side
arrangement of bases along the DNA strand
(e.g., ATTCCGGA). This order spells out the
exact instructions required to create a
particular organism with its own unique traits.
• The genome is an organism’s complete set of
DNA. Genomes vary widely in size: the
smallest known genome for a free-living
organism (a bacterium) contains about
600,000 DNA base pairs, while human and
mouse genomes have some 3 billion. Except
for mature red blood cells, all human cells
contain a complete genome.
• DNA in the human genome is arranged into 46
distinct chromosomes--physically separate
molecules that range in length from about 50
million to 250 million base pairs.
• Each chromosome contains many genes, the
basic physical and functional units of heredity.
• Genes comprise only about 2% of the human
genome; the remainder consists of noncoding
regions
• The human genome is estimated to contain
20,000-25,000 genes.
• The constellation of all proteins in a cell is
called its proteome.
• Studies to explore protein structure and
activities, known as proteomics, will be the
focus of much research for decades to come
and will help elucidate the molecular basis of
health and disease.
• Chromosomes, which range in size from 50
million to 250 million bases
• The human genome contains 3164.7 million
chemical nucleotide bases (A, C, T, and G).
• Almost all (99.9%) nucleotide bases are exactly
the same in all people.
• The functions are unknown for over 50% of
discovered genes.
• http://ornl.gov/sci/techresources/Human_Ge
nome/project/info.shtml