Genome Evolution Course - 2009

Introduction to Evolution and the Human Genome

 

Presentation: (PPT or PDF)

Essay version


Topics

  • The Human Genome
    • Our heredity is contained by the chromosomes.
    • The chromosomes are long sequences of an alphabet of size four.
    • The human genome is ~3.2 billion letters long.
    • GC content is 40% but GC islands occur more than expected by chance.
    • The genome can be thought of as a mosaic of isochors (regions of distinct GC content).
    • The genome contains between 30,000 to 40,000 genes whose coding regions account for 1.5% of the DNA but up to 40% if including the introns.
    • It is estimated that over half of the gene transcripts undergo alternative splicing.
      • Repeats account 44% of the genome.
      • Simple sequence repeats (e.g. TTAGGG)
      • Transposons (LINEs and SINEs)
    • Coding regions are composed of recurring sequence domains.
    • 2% of the genome corresponds to duplicated chromosomal segments in the genome.
    • Many pseudogenes are found in the genome.
    • The mitochondria has a genome too.
  • Molecular life as we know it.
    • All organisms on earth are carbon based.
    • All organisms use the same operating system.
    • All organisms use the same genetic code.
    • A gradient of similarity exists between the sequences of different organisms
  • What is the organizing principle of biology?
    • Aristotle's Great Chain of Being
    • Paley's argument from design
    • Lamarck's theory of transmutation
    • Darwin's theory of evolution by natural selection
    • Argument's against Darwin's theory
    • Lord Kelvin and the age of the earth
    • Fleeming Jenkin and the blending mechanism of inheritance
    • What is the origin of variation?
    • Hershel and "the law of higgledy piggledy"
  • Evolutionary Genomics
    • Genome comparisons allow us to deduce evolutionary changes.
    • The complete genomic sequence of many organisms are available.
    • The mitochondria was once a free living organism.
    • The forces of evolution can be studied by comparing genomes.
    • The development of genomes can be studied by understanding the evolutionary forces.
    • Tracing the evolution of the human genome from its current state back to the universal ancestor

Suggested readings

 

Assignment due October 25th 2009 (at the start of 2nd class)

 

Back to the Genome Evolution Course.

Itai Yanai, yanai@technion.ac.il