Lecture #9
Date _____

Chapter 20~
DNA Technology
& Genomics
O.J. Simpson capital murder case,1/95-9/95
Odds of blood in Ford Bronco not being R. Goldman’s:

6.5 billion to 1

Odds of blood on socks in bedroom not being N. Brown-Simpson’s:

8.5 billion to 1
Odds of blood on glove not being from R. Goldman, N. Brown-Simpson, and O.J.
Simpson:

21.5 billion to 1

Number of people on planet earth:

6.1 billion

Odds of being struck by lightning in the U.S.:

2.8 million to 1

Odds of winning the Illinois Big Game lottery:

76 million to 1

Odds of getting killed driving to the gas station to buy a lottery ticket

4.5 million to 1
 Odds of seeing 3 albino deer at the same time:

85 million to 1

Odds of having quintuplets:

85 million to 1

Odds of being struck by a meteorite:

10 trillion to 1


Recombinant DNA



Def: DNA in which genes
from 2 different sources
are linked
Genetic engineering:
direct manipulation of
genes for practical
purposes
Biotechnology:
manipulation of organisms
or their components to
perform practical tasks or
provide useful products
Bacterial plasmids in gene cloning
DNA Cloning






Restriction enzymes (endonucleases):
in nature, these enzymes protect
bacteria from intruding DNA; they cut up the
DNA (restriction); very specific
Restriction site:
recognition sequence for a particular
restriction enzyme
Restriction fragments:
segments of DNA cut by restriction
enzymes in a reproducable way
Sticky end:
short extensions of restriction
fragments
DNA ligase:
enzyme that can join the sticky ends of
DNA fragments
Cloning vector:
DNA molecule that can carry foreign
DNA into a cell and replicate there (usually
bacterial plasmids)
Restriction Enzymes
QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
Steps for eukaryotic gene cloning





Isolation of cloning vector
(bacterial plasmid) & genesource DNA (gene of interest)
Insertion of gene-source DNA
into the cloning vector using the
same restriction enzyme; bind
the fragmented DNA with DNA
ligase
Introduction of cloning vector
into cells (transformation by
bacterial cells)
Cloning of cells (and foreign
genes)
Identification of cell clones
carrying the gene of interest
Cloning
QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
DNA Analysis & Genomics

PCR (polymerase chain
reaction)
Gel electrophoresis
Restriction fragment
analysis (RFLPs)
Southern blotting
DNA sequencing

Human genome project




Polymerase chain reaction (PCR)



Amplification of any
piece of DNA without
cells (in vitro)
Materials: heat, DNA
polymerase,
nucleotides, singlestranded DNA primers
Applications: fossils,
forensics, prenatal
diagnosis, etc.
DNA Analysis

Gel electrophoresis: separates nucleic acids or proteins on the
basis of size or electrical charge creating DNA bands of the
same length
Restriction fragment analysis



Restriction fragment length polymorphisms (RFLPs)
Southern blotting: process that reveals sequences and
the RFLPs in a DNA sequence
DNA Fingerprinting
DNA Sequencing



Determination of
nucleotide sequences
(Sanger method,
sequencing machine)
Genomics: the study of
genomes based on
DNA sequences
Human Genome
Project
Practical DNA Technology Uses







Diagnosis of disease
Human gene therapy
Pharmaceutical products
(vaccines)
Forensics
Animal husbandry
(transgenic organisms)
Genetic engineering in
plants
Ethical concerns?