Download 13-2 Manipulating DNA

Chapter 13: Genetic Engineering (13-2)
Biologists can now make changes in the DNA code
of living organisms = genetic engineering.
 In the last few decades, molecular biologists
have developed a series of tools that allow them to
extract, edit, and then reinsert DNA into living
organisms.
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Cell opened break down proteinsDNA is
separated
DNA is too large to analyze
It must be examined by fragments
Restriction Enzymes (100+ known) cut the DNA at
a specific sequence of nucleotides…Only cuts if it
matches the sequence precisely
This process creates “sticky ends”
DNA can be separated and analyzed by gel
electrophoresis.
Chapter 13: Genetic Engineering (13-2)
1) Mixture of DNA fragments is placed at one end
of a porous gel
2) Electric current is run through the gel
3) DNA molecules (-) move toward the (+)
4) Smaller pieces move faster, larger move slower
5) Used to locate and identify a particular genes or
used to compare individuals.
 Knowing the sequence of an organism’s DNA
allows researchers to study specific genes, to
compare them with the genes of other organisms,
and to try to discover the functions of different
genes and gene combinations.
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Fluorescent dyes (4 different colors for each type
of nucleotide) attach to fragments of singlestranded DNA.
These are placed in a gel
Show banding patterns and give the sequence
(GATCGAATCGAT…etc)
Chapter 13: Genetic Engineering (13-2)
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It is possible to take a gene from one organism and
attach it to the DNA of another organism—
recombinant DNA
Making many copies of DNA can be done by a
technique known as polymerase chain reaction
(PCR)