GENETIC ENGINEERING TECHNIQUES AND USESDNA, and in some cases RNA, is the primary source of heritable information.

What is Genetic Engineering?Direct manipulation of genetic information.

Allows for direct control of gene expression, and novel combinations of genetic information from different species.

Also enables genetic testing for diseases and identity.

Tool: Restriction EnzymesRestriction enzymes: Cut DNA at specific sequences (making “restriction fragments”)This enables the isolation of different segments of DNA, for introduction in to plasmids, sequencing, or a variety of other studies.

• Separation of DNA molecules based on their size. • Utilizes an electrical field and a gel matrix. Smaller DNA molecules

migrate through the gel faster than larger molecules. • Used to isolate specific genes from within larger samples of DNA, or to

visualize differences in DNA sequences.

Technique: Gel Electrophoresis

Technique: Restriction Enzyme AnalysisRFLP Analysis: Using differences in restriction fragment length to determine identity, identify traits, etc.

Single Nucleotide Polymorphism (SNP)Differences in single base pairs among individuals.

Restriction Fragment Length PolymorphismDifferences in Restriction Fragment Lengths.

Polymerase Chain Reaction• In vitro DNA replication.• Uses: a target sequence of DNA, small primers to

bracket the sequence, a heat-resistant DNA polymerase, and a thermal cycler

• Produces billions of copies of a DNA sequence over a span of hours

DNA Sequencing• Chemical sequencing of the bases in a molecule of DNA.• Modern approaches utilize computers for alignment of genome

fragments (“shotgun sequencing”)• Only a small amount of the human genome codes for proteins

(“exome”)

Transformation• The direct introduction of DNA sequences in to prokaryotic cells. • The DNA sequences are delivered on plasmid vectors. • Used to engineer prokaryotic cells to produce useful proteins. • “transfection”: term for process in eukaryotic cells.

Gene EditingDirect elimination (“knockout”) or replacement of specific DNA sequences.

This has become much easier with the development of the CRISPR system.

• CRISPR refers to unusual DNA sequences that help protect organisms by identifying threats – especially viruses – and attacking them. The name stands for Clustered Regularly Interspaced Short Palindromic Repeats.

Uses of Genetic EngineeringGenetic engineering techniques have many applications.

These applications have many ethical considerations.

• Genetic Recombination• Genetic Testing• Genetically Modified Foods• Pharmaceuticals• Transgenic Animals