In Principle:
Genetic Engineering involves the laboratory manipulation of DNA (MGA2 8-2)
What does a particular region of DNA do?
This may involve isolation of a "gene of interest"
in vivo or in vitro "cloning" of the gene
analysis of the cloned gene
gel electrophoresis
nucleic acid "blotting"
DNA sequencing
mRNA expression
Genetic Engineering involves the laboratory manipulation of DNA (MGA2 8-2)
What does a particular region of DNA do?
This may involve isolation of a "gene of interest"
in vivo or in vitro "cloning" of the gene
analysis of the cloned gene
gel electrophoresis
nucleic acid "blotting"
DNA sequencing
mRNA expression
Biotechnology: “The use of biological systems to create goods & services"
Restriction enzymes [Nobel Prize 1978]
DNA sequencing [Nobel Prize 1980]
Polymerase Chain Reaction (PCR) [Nobel Prize 1993]
For more details, see
Bio2250 - Principles of Genetics
DNA sequencing
in vitro DNA replication reaction copies one strand repeatedly
Provides complete order of bases in a DNA fragment
DNA primer is complementary to 3' end of gene of interest
primers are end-labelled with 32P or 35S
dideoxynucleotide terminators (ddNTPs) (MGA2 8-23)
stop strand growth during replication
four separate reactions terminate at ddA, ddC, ddG, or ddT (MGA 8-22a)
Sequencing gel shows series of partial DNA replications
Sequencing "ladder" is read from bottom to top in an autoradiogram (MGA2 8-22b)
[click here for an of autoradiographic DNA sequencing]
Automated DNA sequencer uses laser fluorometry
ddNTPs are attached to fluorescent dyes
scanning laser & fluorometer "see" fluorescence colours (A C G T)
computer compares colours, "calls sequence" (MGA2 8-24)
Alternative separation methods: Capillary electrophoresis
[click here for an of automated DNA sequencing]
Bio4241 - Sanger et al. 1977
DNA Re-Sequencing Chips for iterative sequencing of populations [PPT presentation]
The ArkChip for multiplex species populations studies
