Genetics, an Overview

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Genetics, an Overview

• Ahad Baghery
• Ahad_Baghery_at_UManitoba.Ca
• PhD Student,
• The University of Manitoba
• Wednesday, Oct. 26, 2005
• Grant Park High School, Winnipeg, MB, Canada

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Outline

• Introduction
• Model organisms
• Cell division Mitosis, Meiosis
• Mendelian principles of genetics
• Key experiments
• DNA, RNA, Transcription, Translation
• PCR A revolution
• Genetic engineeringRecombinant DNA technology
• Applications of genetics
• Branches of Genetics

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Introduction
A Paradox Genetics is Hard Because it is Simple.

• Genetics the scientific study of inheritance and
  its underlying mechanisms.
• Genetics  The study of the structure and
  function of genes and the transmission of genes
  from parents to offspring.

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Model organisms

• Corn
• Yeast
• Rapid Cycling Brassica

• Pea
• Fruit fly
• Arabidopsis

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Cell division Mitosis, Meiosis
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Mendelian principles of genetics
Gregor Mendel, 1822-1864

• Monohybrid cross Law of Segregation
• Dihybrid cross Law of Independence

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Monohybrid cross
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Monohybrid cross
3 Spherical1Wrinkled
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Monohybrid cross
Mendels first law The Principle of
Segregation The two members of a heredity factor
pair segregate from each other in the formation
of gametes.
Now Two members alleles Hereditary factor
gene
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Dihybrid cross
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Dihybrid cross
Mendels second law The Principle of
independence During gamete formation, members of
one heredity factor pair segregate into gametes
independently from other heredity factor pairs.
Now Two members alleles Hereditary factor
gene
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Key experiments

• Morgan 1866-1945
• Griffith 1881-1941

• Avery 1877-1955
• Watson Crick

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Morgans experiment
Conclusion Genes are located on chromosomes.
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Griffiths experiment
Conclusion Some principles should be
transferred from the dead harmful strain into
living harmless strain making transformation.
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Averys experiment
harmful strain
Isolate and purify macromolecules
Proteins RNA DNA
Carbohydrates Lipids
Treat living harmless strain with the purified
chemicals
harmful strain
Only DNA changed the heredity of the living
harmless strain
Conclusion DNA is the principle of
transformation
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Watson Crick
The double helix structure of DNA, the giant
molecule of life.
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DNA, RNA, Transcription, Translation

• DNA replication the process by which new DNA
  molecules (and thus new copies of genetic
  information) are synthesized.
• Transcription the templating process that
  results in synthesis of a strand of RNA
  containing a copy of specific genetic information
  found in DNA.
• Translation synthesis of a polypeptide whose
  amino acid sequence is determined by the
  nucleotide sequence of RNA.

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DNA, RNA, Transcription, Translation
DNA replication
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PCR A revolution

• Polymerase Chain Reaction
• A technique for replicating a specific piece of
  DNA in-vitro , even in the presence of
  excessnon-specific DNA.
• Nobel Prize Kary Mullis 1993
• "DNA Xeroxing"  in vitro (cell-free) DNA
  "cloning"

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Genetic engineeringRecombinant DNA technology

• select the desired gene (or genes) to be inserted
  into the organism
• cut two DNA molecules into fragments with special
  (restriction) enzymes
• splice the fragments together in the desired
  combination
• introduce the new DNA into a living cell for
  replication

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Genetic engineeringRecombinant DNA technology
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Applications of genetics

• Medicine, hereditary diseases gene therapy
  strategies against
• cancer,
• Alzheimer's disease,
• Parkinson's disease,
• heart disease,
• diabetes,
• multiple sclerosis, and
• AIDS.
• Agriculture, Breeding for
• Disease resistance,
• Pest resistance,
• High production yield,
• High quality,
• Stress resistance, and
• Livestock and pets.
• Industry,
• Crime Scene Investigation,
• Paleontology, species evolution, etc.

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Branches of Genetics

• Classical or Mendelian genetics
• Cytogenetics
• Molecular genetics
• Genetic engineering
• Population genetics
• Quantitative genetics
• Genomics study of large-scale genetic patterns
  across the genome for (and in principle, all the
  DNA in) a given species.
• genetics of bacteria, viruses, insects, animals
  and plants, as well as humans

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The End

• Questions?