DNA Technology

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DNA Technology
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Overview

• DNA technology makes it possible to clone genes
  for basic research and commercial applications
• DNA technology is a powerful set of techniques
  that enables biologists to manipulate and analyze
  genetic material
• Genetic engineering is the creation of useful new
  products and organisms using techniques of gene
  manipulation

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The Toolkit for DNA technology includes
restriction enzymes, DNA vectors, and host
organisms

• Either plasmids or bacteriophages can serve as
  vectors (carriers) to introduce recombinant DNA
  molecules into host cells.
• Recombinant DNA is made by inserting a piece of
  DNA containing a gene of interest into the
  plasmid or phage DNA that has been clipped by
  restriction enzymes. In either case, gene cloning
  results when the foreign genes replicate inside
  the host bacterium or other host cell.
• Although bacteria are the most common host
  organisms for cloning, DNA can be introduced
  directly into certain eukaryotic cells as well.

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Recombinant DNA

• Recombinant DNA technology provides a means to
  transplant genes from one species into the genome
  of another.

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Probes

• The selection of a desired gene in recombinant
  DNA can be accomplished using radioactively
  labeled nucleic acid segments of complementary
  sequence called probes.

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Gel electrophoresis

• Gel electrophoresis makes it possible to separate
  and isolate DNA restriction fragments.

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Polymerase Chain Reaction (PCR)

• The polymerase chain reaction (PCR) is a
  technique for quickly making many copies of DNA
  in vitro.

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Hybridization

• Hybridization is a general technique for
  detecting a specific gene or mRNA, by allowing a
  labeled probe with the complementary sequence to
  bind to the target molecule.

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RFLPs

• Restriction fragment length polymorphisms (RFLPs)
  are differences in DNA sequence on homologous
  chromosomes that result in different patterns of
  restrictions fragment lengths. RFLP patterns are
  visualized as bands on gel electrophoresis or
  Southern blots. RFLP analysis has many
  applications, including genetic mapping for basic
  research and diagnosing genetic disorders.

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Progress

• DNA technology is catalyzing progress in many
  fields of biology.
• In vitro mutagenesis can alter a specific gene
  and make it possible for researchers to deduce
  the normal genes function.
• Recombinant DNA technology has enabled
  investigators to answer questions about molecular
  evolution.

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The Human Genome Project

• The Human Genome Projects purpose is to map and
  sequence DNA.
• It is an international research effort
• Project involves linkage mapping, physical
  mapping, and sequencing of the entire human genome