brownbag-science

Genome Size

Genome Size

• Not necessarily correlated with organism complexity
• Homo Sapiens: 3.2 Gb (Giga-bases)
• Marbled lungfish: 130 Gb (Giga-bases)
• Plants often have very large genomes → partially due to redundant information.

The Human Genome… by the Numbers

• ~5% of Human Genome Sequence is Constrained Across Mammals (and Presumed Functional)
  • 5% of 3B Bases=~150M Bases
  • Do NOT Yet Know the Position of these ~150M Functional Bases
  • Lower Bound for the Amount that is Functional
• ~1.5% Encodes for Protein (Genes)
  • Corresponds to ~18-38K Genes
  • Many More than ~22K Different Proteins
  • GoodInventory at Present
• ~3.5% Functional But Non-Coding
  • Gene Regulatory Elements
  • Chromosomal Functional Elements
  • Undiscovered Functional Elements (NOT Yet in Textbooks!)
  • PoorInventory at Presen

Genome comparisons

• Intra-species sequence comparisons
• Inter-species sequence comparisons
  • all humans are > 99.9% identical (0.1% = 3 million differences, ~ 20,000 differences in genes)