genomic sequencing 8

• Genomic sequencing

  Sequencing of nucleotide bases for individual genes and entire genomes
• Identifying base sequences

  Using computer programmes to look for sequences similar to known genes
• Requirements for comparing genomes from different species

  • Sequence data
  • Computer and statistical analyses (bioinformatics)
• Comparison of genomes reveals that many genes are highly conserved across different organisms
• Many genomes have been sequenced, particularly disease-causing organisms, pest species and species that are important model organisms for research
• Evidence for evolutionary history and relationships

  • Phylogenetics
  • Molecular clocks
  • Sequence data
  • Fossil evidence
• Phylogenetics

  The study of evolutionary history and relationships
• Phylogenetic tree

  1. Uses sequence data to study evolutionary relatedness among groups of organisms

  2. Sequence divergence is used to estimate time since lineages diverged
• The three domains of life

  • Bacteria
  • Archaea
  • Eukaryotes
• Molecular clocks

  • Used to show when species diverged during evolution
  • Assume a constant mutation rate
  • Show differences in DNA sequences or amino acids sequences
  • Differences in sequence data between species indicate the time of divergence from a common ancestor
• An individual's genome can be analysed

  • To predict the likelihood of developing certain diseases
  • To select the most effective drugs and dosage to treat their disease (personalised medicine)
• Pharmacogenetics

  The use of genome information in the choice of drugs